Download SKYTRON 3500 O/R Table Service Manual

ELITE SERIES SURGICAL TABLES
MAINTENANCE MANUAL
MODEL ELITE 3500 AND 3500B
AUGUST 2000
Page 65
TABLE OF CONTENTS
SECTION I HYDRAULIC SYSTEM ......................................................................................................................... 1
1-1.
1-2.
1-3.
General ........................................................................................................................................................ 1
Component Operation .................................................................................................................................. 2
a. Motor/Pump Operation ............................................................................................................................ 2
b. Pressure Relief Valve ............................................................................................................................. 2
c. Mini-Valves ............................................................................................................................................. 3
d. Mini-Valve in Neutral Position ................................................................................................................. 3
e. Mini-Valve Right Port Activated .............................................................................................................. 4
f. Mini-Valve Left Port Activated ................................................................................................................ 4
g. Hydraulic Cylinders (Slave Cylinders) ..................................................................................................... 5
h. Elevation Cylinder Return Circuit ............................................................................................................. 7
i. Brake System ......................................................................................................................................... 7
j. Emergency Brake Release ...................................................................................................................... 8
k. Flex/Reflex System ................................................................................................................................. 8
Hydraulic Adjustments ................................................................................................................................. 9
a. Fluid Level. ............................................................................................................................................. 9
b. Bleeding The Hydraulic System .............................................................................................................. 9
c. Pressure Relief Valve ............................................................................................................................. 9
d. Speed Controls ....................................................................................................................................... 9
SECTION II MECHANICAL TABLE ADJUSTMENTS ........................................................................................... 11
2-1.
2-2.
2-3.
Back Section Gear Mesh Adjustment ........................................................................................................ 11
Hydraulic Cylinder Adjustment ................................................................................................................... 11
a. Back Section ........................................................................................................................................ 11
b. Leg Section ........................................................................................................................................... 11
c. Slide and Kidney Lift Cylinders .............................................................................................................. 12
Slide Roller Adjustment .............................................................................................................................. 12
SECTION III HYDRAULIC TROUBLESHOOTING ................................................................................................. 13
3-1.
3-2.
3-3.
3-4.
3-5.
3-6.
3-7.
3-8.
3-9.
3-10.
3-11.
3-12.
3-13.
Precautions ............................................................................................................................................... 13
Troubleshooting Notes ............................................................................................................................... 13
ELEVATION DIAGNOSIS CHART ............................................................................................................. 14
TRENDELENBURG DIAGNOSIS CHART .................................................................................................. 15
LATERAL - TILT DIAGNOSIS CHART ...................................................................................................... 16
BACK SECTION DIAGNOSIS CHART ....................................................................................................... 17
FLEX SYSTEM DIAGNOSIS CHART ......................................................................................................... 18
LEG SECTION DIAGNOSIS CHART .......................................................................................................... 19
KIDNEY LIFT DIAGNOSIS CHART ........................................................................................................... 20
SLIDE DIAGNOSIS CHART ....................................................................................................................... 21
BRAKE CIRCUIT DIAGNOSIS CHART ...................................................................................................... 22
Flexible Hose Identification and Placement ................................................................................................ 23
Kidney Lift System ..................................................................................................................................... 24
SECTION IV ELECTRICAL SYSTEM ................................................................................................................... 26
4-1.
4-2.
4-3.
General ...................................................................................................................................................... 26
Components .............................................................................................................................................. 26
Battery Model Components ......................................................................................................................... 26
SECTION V ELECTRICAL SYSTEM TROUBLESHOOTING ................................................................................ 28
5-1.
5-2.
5-3.
5-4.
5-5.
Troubleshooting Notes ................................................................................................................................
Main Switch ................................................................................................................................................
Pendant Control ..........................................................................................................................................
Relay Box ...................................................................................................................................................
Solenoids ....................................................................................................................................................
28
28
29
30
32
Although current at time of publication, SKYTRON's policy of continuous development makes this manual subject to change
without notice.
Page 62
03/02
TABLE OF CONTENTS (cont.)
SECTION V ELECTRICAL SYSTEM TROUBLESHOOTING (cont.) ..................................................................... 28
5-6.
5-7.
5-8.
Motor/Pump Assembly ............................................................................................................................... 33
Return-to-Level Micro-Switches .................................................................................................................. 35
Return/Inhibit System Troubleshooting ....................................................................................................... 36
SECTION VI -3500B- BATTERY MODEL, ELECTRICAL TROUBLESHOOTING ................................................. 42
6-1.
6-2.
6-3.
6-4.
6-5.
6-6.
6-7.
6-8.
6-9.
6-10.
6-11.
6-12.
6-13.
6-14.
General ...................................................................................................................................................... 42
Troubleshooting Notes ................................................................................................................................ 42
Main Switch ................................................................................................................................................ 42
Batteries .................................................................................................................................................... 44
Battery Charging Box/AC120V Transformer ............................................................................................... 44
Switch-Over Relay ..................................................................................................................................... 46
Pendant Control .......................................................................................................................................... 47
Auxiliary Switches ..................................................................................................................................... 48
Relay Box ................................................................................................................................................... 48
Main Wire Harness Continuity Test ............................................................................................................ 50
Solenoids .................................................................................................................................................... 51
Motor/Pump Assembly ............................................................................................................................... 52
Return-to-Level Micro-Switches .................................................................................................................. 53
Return/Inhibit System Troubleshooting ....................................................................................................... 54
SECTION VII -3500B- BATTERY MODEL, ELECTRICAL SYSTEM ADJUSTMENTS ......................................... 60
7-1.
Relay Box Adjustments .............................................................................................................................. 60
Page 63
SECTION I HYDRAULIC SYSTEM
1-1. General
Electro-Hydraulic System
The hydraulic system (with the exception of the
hydraulic cylinders and hoses) is contained within
the base of the table. The hydraulic valves and
pump are electrically controlled by the use of a
hand-held push button pendant control. The power
requirements for the table are 120 VAC, 5 amp, 60
Hz.
The table contains the following components. Refer to the block diagram (figure 1-1) for relationship.
Figure 1-1. Hydraulic Block Diagram
Page 1
a. Oil Reservoir - Main oil supply. Approximately
two quarts.
b. Motor/Pump Assembly - A positive displacement gear type pump provides the necessary oil
pressure and volume.
c. Pressure Relief Valve - Provides an alternate oil
path when the hydraulic cylinders reach the end of
their stroke.
d. Electro/Hydraulic Mini-Valve Assemblies -These
direct the fluid to the appropriate hydraulic cylinders.
e. Hydraulic Lines, Fittings, Connections - They
provide a path for the hydraulic oil.
f. Hydraulic Cylinders - They convert the hydraulic
fluid pressure and volume into mechanical motion.
b. Pressure Relief Valve
This device provides an alternate oil path when the
hydraulic cylinders reach the end of their stroke
and the pump continues to run. If this path were not
provided, the pump motor would stall because the
oil cannot be compressed. The pressure relief
valve is directly connected to the mini-valve bodies
and shares both the common internal main pressure oil galley, and the return oil galley, that internally connect to the reservoir.
The main component of the valve is an adjustable
spring loaded plunger that is pushed off from its
seat by the oil pressure. The oil then flows back into
the reservoir. Turning the adjustment nut clockwise increases the amount of oil pressure required
to open the valve, and turning it counterclockwise
decreases the amount of oil pressure. (See adjustment section for specification.)
1-2. Component Operation
a. Motor/Pump Operation
PRESSURE RELIEF
ADJUSTMENT NUT
The motor/pump assembly is a gear type pump that
provides the oil pressure and volume for the entire
hydraulic system. The pump has an inlet side and
an outlet side. The inlet side is connected to the
reservoir which provides the oil supply. The reservoir has a very fine mesh screen strainer which
prevents foreign material from entering the oil
system.
The output line of the pump is connected to the main
oil galley which is internal and common to all the
hydraulic mini-valves and pressure relief valve.
Also, common to the hydraulic mini-valves and
pressure relief valve is an oil galley that internally
connects to the oil reservoir to provide a return path
for the hydraulic oil. See figure 1-2.
PUMP
OUTLET
MAIN RETURN
OIL GALLEY
(INTERNAL)
PRESSURE
GAUGE
Figure 1-3. Pressure Relief Valve Not
Functioning
PRESSURE RELIEF
ADJUSTMENT NUT
MAIN PRESSURE
OIL GALLEY
(INTERNAL)
MINI-VALVES
PRESSURE
GAUGE
MOTOR/PUMP
ASSEMBLY
SPRING LOADED
PLUNGER
PRESSURE
RELIEF VALVE
PUMP INLET
OIL
RESERVOIR
Figure 1-2.
Page 2
SPRING LOADED
PLUNGER
Figure 1-4. Pressure Relief Valve Functioning
c. Mini-Valves
The operation of the mini-valves is identical for all
table functions except the elevation and Single
Action Brake circuits. These two hydraulic circuits
use a 3-way (single check valve) type mini-valve.
All other functions use a 4-way (dual check valve)
type mini-valve.
Either type mini-valve is controlled by two pushing
type, electrically operated solenoids. The solenoids push the spool valve (located in the lower
portion of the valve) one way or the other. This
motion opens the main supply galley (which has
pump pressure) allowing the oil to flow through the
various parts of the mini-valve to the function. The
spool valve also opens an oil return circuit which
allows the oil to return to the oil reservoir.
The main components of the mini-valve and their
functions are listed below:
1. Spool Valve - Opens the main oil galley
(pump pressure) to either mini-valve outlet depending on which direction the spool valve is pushed.
Also it provides a return path for the oil returning
back into the reservoir.
2. Pilot Plunger - There are two plungers in a
four-way mini-valve (one in a 3-way mini-valve),
one under each check valve. The purpose of the
pilot plungers is to mechanically open the return
check valve allowing the oil to return back into the
reservoir.
Also, by using this control method, it doesn’t matter
what size cylinder and piston is used because the
speed can be controlled by restricting the return oil.
If the pump puts out more volume to a certain slave
cylinder than the speed control is allowing to go
back to the reservoir, the pressure relief valve
provides an alternate path for the pump oil.
d. Mini-Valve in Neutral Position
(No fluid flow) See figure 1-5.
1. Spool Valve Centered - This closes off both
oil pressure and oil return galleys.
2. Pilot Plungers Both Closed -The pilot plungers control the opening of the check valves. If they
are closed, the check valves must be closed.
3. Check Valves - Both check valves are
closed trapping the oil in the cylinder and oil lines.
4. Speed Adjustment - When the mini-valve is
in the neutral position, the speed adjustment does
not affect anything because there is not any oil flow.
OIL LINE
BALL
VALVE
OIL LINE
SPEED
CONTROL
PILOT
PLUNGER
CHECK
VALVE
3. Check Valve - Two are provided in each
four-way mini-valve to seal the oil in the cylinders
and oil lines and prevent any movement of the table.
One check valve is provided in a 3-way mini-valve.
4. Speed Adjustments - There are two speed
adjustments in each mini-valve. They are needle
valve type controls which restrict the volume of oil
returning back into the reservoir, thereby controlling the speed of the table surface movement. A 3way mini-valve has only one speed adjustment.
OIL GALLERY OIL RETURN
(PRESSURE)
(RETURN)
SPOOL
VALVE
SOLENOID
PISTON
Figure 1-5. Mini-Valve in Neutral Position
The speed controls are always located in the return
oil circuit. This prevents uncontrolled movement of
the piston in the slave cylinder due to one side of the
piston being loaded with hydraulic pressure and
the other side having no load.
Page 3
e. Mini-Valve Right Port Activated
(See figure 1-6)
Slave Cylinder Piston Moves to Left
Right Mini-Valve Port is Supply Line
Left Mini-Valve Port is Return Line
INLET
f. Mini-Valve Left Port Activated
(See figure 1-7.)
Slave Cylinder Piston Moves to Right
Left Mini-Valve Port is Supply Line
Right Mini-Valve Port is Return Line
OUTLET
Figure 1-6. Mini-Valve Right Port Activated
Figure 1-7 Mini-Valve Left Port Activated
1. Spool Valve - Pushed to the left by electric
solenoid. This opens the internal oil pressure galley allowing the fluid to go through the check valve
and on to the cylinder. Also, the spool valve opens
the oil return line providing an oil path through the
internal oil galley back to the reservoir.
1. Spool Valve -Pushed to the right by electric
solenoid. This opens the internal oil pressure galley
allowing the fluid to go through the check valve and
on to the cylinder. Also, the spool valve opens the
oil return line providing an oil path through the
internal oil galley back to the reservoir.
2. Pilot Plunger Valve - Left pilot plunger valve
is pushed up by the incoming oil pressure mechanically opening the check valve located above it in
the return circuit. This action allows the oil from the
left side of the slave cylinder to go back into the
reservoir. The right pilot plunger valve is not
affected in this operation mode.
2. Pilot Plunger Valve - Right pilot plunger valve
is pushed up by the incoming oil pressure mechanically opening the check valve located above it in
the return circuit. This action allows the oil from the
right side of the slave cylinder to go back into the
reservoir. The left pilot plunger valve is not affected
in this operation mode.
3. Check Valves - Both check valves are
opened in this operation mode. The right check
valve is pushed open by the oil pressure created by
the pump. The oil then continues to go through the
lines and pushes the slave cylinder piston to the
left. At the same time, the left check valve is held
open mechanically by the pilot plunger providing a
return path for the oil through the mini-valve back to
the reservoir.
3. Check Valves - Both check valves are
opened in this operation mode. The left valve is
pushed open by the oil pressure created by the
pump. The oil then continues to go through the
lines and pushes the slave cylinder piston to the
right. At the same time, the right check valve is held
open mechanically by the pilot plunger providing a
return path for the oil through the mini-valve back to
the reservoir.
4. Speed Adjustment - The right speed control
(output side) does not have any effect in this
operation mode because the oil is routed around
the speed adjustment through a by-pass valve and
then to the output port. The left speed adjustment
controls the speed of the table function by restricting the amount of oil going back into the reservoir.
4. Speed Adjustment - The left speed control
(output side) does not have any effect in this operation mode because the oil is routed around the
speed adjustment through a by-pass valve and
then to the output port. The right speed adjustment
controls the speed of the table function by restricting the amount of oil going back to the reservoir.
Page 4
g. Hydraulic Cylinders (Slave Cylinders)
There are several different types of hydraulic cylinders used in the table that activate the control
functions. With the exception of the elevation and
brake cylinders, all operate basically the same
way. The control functions are listed below: (See
figure 1-8.).
Trendelenburg--1, double action cylinder
Back Section--2, double action cylinders
Leg Section--2, double action cylinders
Slide--1, double action cylinder
Kidney Lift--2, double action cylinders
Lateral Tilt--1, double action cylinder
Elevation--1, single action cylinder
Brakes--4, single action cylinders
BACK SECTION
CYLINDER
LATERAL TILT
CYLINDER
LEG SECTION
CYLINDER
O-RING
O-RING
PISTON
RAM
HYDRAULIC LINE
Figure 1-9. Back Section Cylinder
2. Slide Cylinder Assembly - This cylinder
arrangement has two pistons, one on each end of
a ram which has rack gear teeth cut into its top
surface. These teeth mesh with a gear arrangement that drives a rack gear connected to the
bottom of the side frame.
When hydraulic fluid is pumped into one side of the
cylinder, the pistons are pushed in one direction,
the gear arrangement rotates and causes the table
top to slide. Oil pressure can be applied to either
piston, making the table slide end for end. See
figure 1-10.
RACK GEAR
SLIDE
CYLINDER
RAM
KIDNEY LIFT
CYLINDER
TRENDELENBURG
CYLINDER
ELEVATION
CYLINDER
O-RINGS
O-RINGS
PISTONS
Figure 1-8. Cylinder Placement
1. Trendelenburg, Back Section and Leg Section Cylinders - The double action cylinders are
closed at one end and have a movable piston with
hydraulic fluid on both sides. Connected to this
piston is a ram or shaft that exits out of the other end
of the cylinder. Through the use of either a ball and
socket, a gear, or clevis and pin arrangement, the
ram is connected to a movable table surface.
The movable surface can be moved one way or
the other by pumping hydraulic fluid into the cylinder on either side of the piston. Obviously, if oil is
pumped into one side of the cylinder, a return path
must be provided for the oil on the other side. See
figure 1-9.
Figure 1-10. Slide Cylinder Assy.
3. Kidney Lift Cylinders - The two kidney lift
cylinders are similar to the slide cylinder in that the
ram has rack gear teeth cut into the top surface. ORings on each end of the ram allow the ram to also
serve as the pistons.
The rack teeth cut into the top of the ram meshes
with a pinion gear. This gear meshes with other
gears to supply the up or down drive for the kidney
lift bars, depending on which direction the oil is
pumped into the cylinder. See figure 1-11.
Page 5
The cylinder is set in the center of the elevation
main column. The two stage cylinder is elevated by
the driven force of the oil pressure. When lowering,
the oil that is accumulated in the cylinder is returned
to the oil reservoir through the mini-valve due to the
table top weight.
A slider support assembly is used to support the
weight of the upper table section. A stainless steel
shroud covers the flexible hydraulic hoses and
slider. See figure 1-13.
RAM
PINION
GEAR
O-RINGS
O-RINGS
ELEVATION
CYLINDER
Figure 1-11. Kidney Lift Cylinder Assembly
4. Lateral Tilt Assembly - The lateral tilt assembly consists of two cylinders, pistons and connecting rods. The connecting rods attach to the lateral
tilt lever which connects to the table center column
assembly. The cylinder housing attaches to the
table top and is attached to the center column
assembly by pivots. See figure 1-12.
The pistons and connecting rods are attached to a
non-movable surface. Therefore, when hydraulic
fluid is pumped into one side, the cylinder housing
itself moves around the lateral tilt lever causing the
table top to tilt to one side.
To tilt the table top in the opposite direction, fluid is
pumped into the opposite cylinder.
O-RINGS
CONNECTING RODS
SHROUD
PRIMARY
PISTON
ELEVATION
COLUMN
SECONDARY
PISTON
Figure 1-13. Elevation Cylinder Assembly
6. Brake Cylinders - The brake cylinders are
single action type similar to the elevation cylinder.
The movable piston's ram is connected to a brake
pad. See figure 1-14. Oil pumped into the top of the
cylinder pushes the piston down raising the table
base off its casters. An internal return spring on the
bottom of the piston, pushes the piston up to return
the oil through the mini-valve to the reservoir.
PISTON
OIL LINE
PISTON
LATERAL
TILT LEVER
RETURN
SPRING
O-RINGS
PISTON
Figure 1-12. Lateral Tilt Cylinder Assembly
5. Elevation Cylinder - This single action cylinder does not have hydraulic fluid on both sides of
the piston. It depends on the weight of the table top
assembly to lower it.
Page 6
BRAKE
PAD
RAM
Figure 1-14. Brake Cylinder
h. Elevation Cylinder Return Circuit
1. Single action slave cylinders (4 each).
A three-way (single check valve type) mini-valve
controls both the elevation and return circuits. The
elevation circuit operation within the mini-valve is
identical to the operation of the four-way valves
previously described (inlet pressure opens the
check valve allowing the oil to enter the cylinder). In
the return position, inlet pressure pushes the pilot
plunger up and opens the return check valve. See
figure 1-15. The open check valve allows a path for
the oil in the elevation cylinder to return to the
reservoir. When the pilot plunger valve is opened,
the continuing pump pressure opens the pressure
relief valve which provides a return oil path to the
reservoir.
2. 3-way (single check valve type) mini-valve.
3. Manually controlled emergency brake release.
4. Plumbing terminal, flexible hoses, copper
lines and "O" rings.
5. Portions of the electrical system.
BRAKE
CYLINDERS
BRAKE
MINI-VALVE
EMERGENCY
BRAKE
RELEASE
The mini-valve used in the elevation circuit contains only one check valve (all four-way minivalves use two check valves). The check valve is
used to trap the oil in the elevation cylinder thereby
supporting the table top. When the top is being
lowered the check valve is mechanically held open
by the pilot plunger through pump pressure.
PRESSURE
RELIEF
VALVE
BACK
LEG
KIDNEY
SLIDE
ELEVATION
CYLINDER
SPEED
CONTROL
PILOT
PLUNGER
CHECK
VALVE
Figure 1-16. Brake System Block Diagram
SPOOL
VALVE
PRESSURE
RELIEF VALVE
RESERVOIR
Figure 1-15. Elevation Return Circuit
i. Brake System
The brake system consists of the following components: (figure 1-16)
Each corner of the cast-iron table base has a
hydraulic brake cylinder. These single action cylinders are hydraulically connected in parallel to the
mini-valve and all four are activated together. It is
normal for one corner of the table to raise before the
others due to the weight distribution of the table.
An electronic timer in the relay box is activated
when any function on the pendant control is
pushed momentarily. The pump/motor and brake
system mini-valve is activated and the brake cylinders are completely set. The electronic timer runs
for approx. 8-10 seconds.
The brakes are released by pushing the BRAKE
UNLOCK button momentarily. An electronic timer
in the relay box activates the brake function hydraulic mini-valve and pump/motor.
Page 7
When activated, the return hydraulic circuit operates similar to the elevation cylinder return circuit.
Return springs inside the single action brake cylinders retract the brake pads and provide the pressure to return the hydraulic oil back to the reservoir.
The electronic timer operates the return circuit for
approximately 8-10 seconds.
j. Emergency Brake Release
The emergency brake release is simply a manually
operated bypass valve connected in parallel to the
brake cylinders and the oil reservoir. See figure 117. When the valve is opened (turned counterclockwise) a return circuit for the brake hydraulic
fluid is opened. The return springs force the pistons
up pushing the hydraulic oil back into the reservoir
and retracting the brake pads.
1. The brakes will release slowly- depending
on how loose the valve is, this could take anywhere
from a few minutes to several hours.
2. None of the table functions will operate
properly if the valve is wide open. All of the
hydraulic fluid from the pump is simply pumped
through the brake bypass circuit because that is
the easiest path for the oil to follow.
k. Flex/Reflex System
The Flex/Reflex system has a mini-valve which
connects the trendelenburg and back section hydraulic systems in a series. When FLEX is activated by the pendant control, the Flex/Reflex minivalve opens the oil pressure path to the Reverse
Trendelenburg piston. The return oil path from the
trendelenburg piston is routed through the back
section cylinder to the mini-valve return port. See
figure 1-18.
TREND
EMERGENCY BRAKE
RELEASE LEVER
Figure 1-17.
BACK UP
REV. TREND
BACK
DOWN
IMPORTANT
•The emergency brake release valve
must be tightened securely when not in
use.
•If the emergency brake release valve
has been operated, the UNLOCK button on the pendant control may have to
be pressed before brakes will lock
again.
If the emergency brake release valve is open or
loose, two conditions could occur:
Page 8
PLUMBING
TERMINAL
FLEX/REFLEX
MINI-VALVE
Figure 1-18. Flex/Reflex System
1-3. Hydraulic Adjustments
c. Pressure Relief Valve
a. Fluid Level.
The pressure relief valve is adjusted by turning the
adjustment nut until the desired pressure is reached.
The fluid level should be approximately 1/2" below
the filler hole or gasket surface. If additional fluid is
needed, remove the filler vent cap with a phillips
screwdriver and add fluid through this opening
using a funnel. See figure 1-19.
NOTE
The elevation cylinder should be completely down and all the other control
functions in their neutral position when
checking oil level.
To adjust:
1. Remove the plumbing bolt securing the
brake system line to the pressure relief valve and
attach a hydraulic pressure gauge as shown in
figure 1-20 using a long 6mm plumbing bolt.
PRESSURE
RELIEF VALVE
PRESSURE
GAUGE
FILLER VENT
FILLER
CAP
RESERVOIR
OPENING
LONG 6 mm
PLUMBING
BOLT
Figure 1-19.
The type of oil that should be used is Mobil DTE #25
or equivalent. This is a very high quality hydraulic
oil. The table requires approximately two quarts of
oil to operate properly.
b. Bleeding The Hydraulic System
To purge the air from the hydraulic system, operate
each function back and forth at least two or three
times.
NOTE
Whenever a hydraulic line or component is replaced, bleed the air out of
the lines using the pump pressure before making the final connection. Then
operate the function until it stalls in both
directions.
Figure 1-20.
2. Raise the table top until the piston reaches
the end of its stroke and stalls. Observe reading
on pressure gauge and turn the adjustment nut
(clockwise to increase oil pressure, counterclockwise to decrease) until desired reading is
obtained. Pressure should be 80KG/CM2 -1138
PSI.
d. Speed Controls
The speed controls restrict the volume of oil returning back to the reservoir thereby controlling the
speed of each control function.
All four-way mini-valves, have two speed controls
located in the ends of each valve body. All threeway mini-valves have only one speed control.
Page 9
One speed control adjusts one direction of a
particular function and the opposite speed control
adjusts the other direction. They are adjustable by
using a small straight blade screwdriver and
turning the adjustment screw clockwise to decrease the speed and counterclockwise to
increase the speed. Refer to figure 1-21.
TILT RIGHT
TABLE DOWN
TREND
REFLEX
BRAKE
BACK UP
LEG DOWN
KIDNEY UP
SLIDE
HEAD
A pressure gauge should be used to set the speed
of the back section, trendelenburg and flex control
functions.
To adjust:
1. Attach the pressure gauge onto the main oil
galley as shown in figure 1-20.
2. The gauge should read the following values
when operating the various control functions in
either direction. Turn the speed controls until
desired values are obtained.
Back Section
Up
Dn
65KG/CM2 -925PSI
65KG/CM2-925PSI
Trendelenburg
Up
Dn
65KG/CM2 -925PSI
65KG/CM2 -925PSI
REV.
TREND
SLIDE
FOOT
TILT LEFT
FLEX
BACK DOWN
KIDNEY
DOWN
LEG UP
Flex
70KG/CM2 -995PSI
Reflex
70KG/CM2 -995PSI
Figure 1-21.
NOTE
Any control function should move in either direction at the same rate. If the rate of a certain function
is too slow, open the speed control slightly and
recheck. Use the second hand on a watch and time
a particular function. Match that time in the opposite
direction by opening or closing the speed control.
Approximate operating times are as follows:
Elevation Down
Lateral Tilt
Leg-Up
Leg-Down
Kidney Lift
Slide
Page 10
30 seconds
7 seconds
25 seconds
15 seconds
7 seconds
20 seconds
When adjusting Flex/Reflex speed controls, set Reflex last.
Elevation - There is not a speed adjustment for
raising the table. The speed control will only affect
the rate of descent and it should equal the rate of
elevation.
SECTION II MECHANICAL TABLE ADJUSTMENTS
2-1. Back Section Gear Mesh Adjustment
The gear mesh is adjusted by the use of an eccentric cam. This cam moves the gear teeth closer
together to eliminate gear lash. This adjustment
arrangement compensates for any wear between
the gears that might occur.
To adjust:
Loosen the cam locking allen set screw. Use an
allen wrench to rotate the eccentric cam. See
figure 2-1. Tighten the set screw when adjustment
is complete.
ECCENTRIC
CAM
SET SCREW
Any twisting or flexing of the back section as it
approaches the stalled position indicates that one
of the cylinders is not reaching its fully extended
position at the same time as the other. This
condition would require an adjustment.
To adjust:
Remove the top from the seat section for access to
the locking set screws.
Loosen the set screw located above the eccentric
cam in each side frame. Use an allen wrench to
turn the cylinder eccentric cams as required to shift
either cylinder fore or aft as needed so no twisting
or flexing of the back section is observed when it is
stalled in the full up position. Tighten the set screws
and replace the seat section top when proper
adjustment has been achieved. See figure 2-2.
BACK SECTION
SEAT SECTION TOP
ALLEN
WRENCH
Figure 2-1. Eccentric Cam Adjustment
SET
SCREW
BACK SECTION CYLINDER
ECCENTRIC CAM
2-2. Hydraulic Cylinder Adjustment
Back & Leg Sections
The hydraulic cylinder rams that control both the
back and leg sections must move together so that
these sections are not twisted when operated. This
is accomplished by the use of eccentric cams that
move the cylinder bodies fore and aft to adjust their
effective stroke.
NOTE
Adjust gear mesh before adjusting eccentric cams for the back section.
a. Back Section
Position the back section all the way up until it
stalls. Both sides of the back section should stop
moving at the same time and should not show any
signs of twisting.
Figure 2-2. Back Section Adjustment
b. Leg Section
Position the leg section all the way up until it is
horizontal. Both sides of the leg section should
stop moving at the same time and should not show
any signs of twisting.
Any twisting or flexing of the leg section as it
approaches the stalled position indicates that one
of the cylinders is not reaching its fully extended
position at the same time as the other and an
adjustment is required.
Page 11
To adjust:
2-3. Slide Roller Adjustment
Loosen the cam locking set screws located on the
bottom of the cylinder mounting plates inside the
table side frames. Use an allen wrench to turn the
cylinder eccentric cams as required to shift either
cylinder fore or aft as needed so no twisting or
flexing of the leg section is observed when it is
stalled in the horizontal position. Tighten set screws
when proper adjustment is achieved. See figure 23.
The pivot pins on the slide rollers are eccentric
cams. The rollers can be adjusted if required to
maintain proper top slide operation.
To adjust:
Remove the Seat section top, the hose cover and
the right and left lateral tilt frame covers for access
to the top rollers.
1. Align the table top so the rollers to be
adjusted are contacting the slide bars.
LEG SECTION
LEG SECTION CYLINDER
ECCENTRIC CAM
SET SCREW
Figure 2-3. Leg Section Adjustment
c. Slide and Kidney Lift Cylinders
If the Slide or Kidney Lift cylinder has been removed, the distance from the end of the piston to
the end of the cylinder housing must be checked to
make sure the functions will operate correctly.
2. Loosen the adjustment cam set screw and
adjust the roller using an 8mm Allen wrench. See
figure 2-5. To avoid any possible binding in the slide
mechanism, adjust the roller on the opposite side of
the table in the same manner (cam turned toward
same end of table on each side).
3. Adjust rollers so top slides smoothly with no
up or down movement of the table top.
4. When adjustment is complete, tighten set
screws, replace covers and top section.
SET SCREW
With table top centered, the distance from the end
of the Slide piston to end of cylinder is:
Head End - 82 mm
Foot End - 120 mm
The table top should slide 7-1/2" toward the head
and 13-1/4" toward the foot when positioned properly. Refer to figure 2-4.
SLIDE
ROLLER
With Kidney Lift all the way down, the distance
from the end of the Kidney Lift piston to end of
cylinder is:
Head End - 82 mm
Tail End - 11 mm
8mm
ALLEN
WRENCH
13-1/4"
SLIDE
TOWARD
FOOT
7-1/2"
SLIDE
TOWARD
HEAD
120mm
82mm
Figure 2-4.
Page 12
Figure 2-5.
SECTION III HYDRAULIC TROUBLESHOOTING
3-1. Precautions
Before attempting to troubleshoot any hydraulic
problem on the table, please read through the precautions and notes below.
CAUTION
When disconnecting any of the hydraulic lines, fittings, joints, hoses, etc., for
the following control functions, be sure
these table surfaces are in their down
position or completely supported.
Elevation
Back Section
Leg Section
Kidney Lift
When working on the trendelenburg or
lateral tilt hydraulic circuits, be sure to
support the table top. When working on
the brake system make sure the brakes
are completely retracted.
CAUTION
Failure to follow these precautions may
result in an uncontrolled oil spray and
damage to the table or personal injury.
3-2. Troubleshooting Notes
When troubleshooting a table malfunction, first
determine the following:
1. Does the problem affect all control functions?
2. Does the problem affect only one control
function?
3. If the problem affects one control function is
it in both directions?
Once the problem has been determined, concentrate on that particular hydraulic circuit or control
function.
Listed below are the hydraulic components that
are common with all hydraulic circuits. If there is a
problem with any of them, it could affect all control
functions.
1. Motor/Pump Assembly
2. Reservoir
3. Pressure Relief Valve
4. Certain Oil Lines and Galleys
If there was a problem in the following components,
only one control function would normally be affected.
1. Mini-Valve
2. Slave Cylinder
3. Oil Lines
NOTE
Whenever a hydraulic line or component is replaced, bleed the air out of the
lines using the pump pressure before
making the final connection. After all
connections are tight, cycle the control
function back and forth two or three
times to purge the remaining air from the
system.
IMPORTANT
When installing new "O" rings use hydraulic oil to thoroughly lubricate the "O"
rings and cylinder. Keep everything
clean.
Each complete oil circuit is shown on the following
pages. When troubleshooting a particular function,
refer to the appropriate oil circuit diagram and the
list of possible problems.
4. Is the problem intermittent?
5. Is the problem no movement of a table
surface or does the table surface lose position?
Page 13
3-3. ELEVATION DIAGNOSIS CHART
Problem
Table will not elevate properly
Reason
Pressure Relief Valve Not Set Properly
Low on Oil
Spool Valve Not Centered or Adjusted Properly
Defective Pump
Defective Mini-Valve
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
Table will not descend properly
Incorrect Speed Adjustment
Bad Check Valve
Spool Valve Not Centered
Defective Solenoid or Pendant Control
Table loses elevation
Bad Check Valve
Leaking Mini-Valve
Loose Fittings, Joints, Hoses
Leaking "O" Ring Inside Cylinder
PRIMARY
PISTON
O-RING
COPPER
LINE
PLUMBING
TERMINAL
SECONDARY
PISTON
O-RING
CHECK
VALVE
SPEED
CONTROL
INTERNAL OIL
FROM PUMP
MINI-VALVE
INTERNAL OIL RETURN
TO RESERVOIR
Figure 3-1. Elevation Circuit
Page 14
FLEXIBLE
HOSE
3-4. TRENDELENBURG DIAGNOSIS CHART
Problem
Trendelenburg function moves improperly
Reason
Incorrect Speed Adjustment
Spool Valve Not Centered or Adjusted Properly
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
Trendelenburg function chatters or loses position
Defective or Dirty Check Valve
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
TRENDELENBURG
CYLINDER ASSEMBLY
COPPER
LINES
PISTON
PLUMBING
TERMINAL
O-RING
CHECK
VALVE
SPEED
CONTROL
MINI-VALVE
INTERNAL OIL RETURN
TO RESERVOIR
INTERNAL OIL
FROM PUMP
Figure 3-2. Trendelenburg Circuit
Page 15
3-5. LATERAL TILT DIAGNOSIS CHART
Problem
Lateral tilt function moves improperly
Reason
Incorrect Speed Adjustment
Spool Valve Not Centered or Adjusted Properly
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Defective Solenoid
Defective Relay Box or Pendant Control
Lateral tilt function chatters or loses position
Defective or Dirty Check Valves
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
LEFT TILT
CYLINDER
HOUSING
CYLINDER CAP
FITTING
PISTON O-RING
COPPER
LINES
PLUMBING
TERMINAL
CHECK
VALVE
SPEED
CONTROL
MINI-VALVE
INTERNAL OIL RETURN
TO RESERVOIR
INTERNAL OIL
FROM PUMP
Figure 3-3. Lateral Tilt Circuit
Page 16
RIGHT TILT
3-6. BACK SECTION DIAGNOSIS CHART
Problem
Back Section function moves improperly
Reason
Incorrect Speed Adjustment
Spool Valve Not Centered or Adjusted Properly
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
Back Section function chatters or loses position
Defective or Dirty Check Valves
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
BACK SECTION
CYLINDER ASSEMBLY
NOTE: ONE SIDE
SHOWN FOR CLARITY
UP CIRCUIT
DOWN CIRCUIT
COPPER
LINES
PLUMBING
TERMINAL
CHECK
VALVE
SPEED
CONTROL
MINI-VALVE
INTERNAL OIL RETURN
TO RESERVOIR
INTERNAL OIL
FROM PUMP
Figure 3-4. Back Section Circuit
Page 17
3-7. FLEX SYSTEM DIAGNOSIS CHART
Problem
Back Section or Trendelenburg function moves
improperly
Reason
Incorrect Speed Adjustment (Trendelenburg, Back
Section or Flex - check with gauge)
Spool Valve Not Centered or Adjusted Properly
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
IMPORTANT
If Flex System does not function properly, check the back section and trendelenburg functions before adjusting
the flex system.
Back Section or Trendelenburg function chatters
or loses position
Defective or Dirty Check Valves
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
BACK SECTION
CYLINDER ASSEMBLY
TRENDELENBURG
CYLINDER ASSEMBLY
UP CIRCUIT
DOWN CIRCUIT
TO TRENDELENBURG
MINI-VALVE
PISTON
O-RING
PLUMBING
TERMINAL
TO BACK SECTION
MINI-VALVE
CHECK
VALVE
SPEED
CONTROL
MINI-VALVE
INTERNAL OIL RETURN
TO RESERVOIR
INTERNAL OIL
FROM PUMP
Figure 3-5. Flex System Circuit
Page 18
3-8. LEG SECTION DIAGNOSIS CHART
Problem
Leg function moves improperly
Reason
Incorrect Speed Adjustment
Spool Valve Not Centered or Adjusted Properly
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
Leg function chatters or loses position
Defective or Dirty Check Valves
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
LEG SECTION
CYLINDER ASSEMBLY
NOTE: ONE SIDE
SHOWN FOR CLARITY
DOWN CIRCUIT
UP CIRCUIT
COPPER
LINES
PLUMBING
TERMINAL
CHECK
VALVE
SPEED
CONTROL
MINI-VALVE
INTERNAL OIL RETURN
TO RESERVOIR
INTERNAL OIL
FROM PUMP
Figure 3-6. Leg Section Circuit
Page 19
3-9. KIDNEY LIFT DIAGNOSIS CHART
Problem
Kidney Lift moves improperly
Reason
Incorrect Speed Adjustment
Spool Valve Not Centered or Adjusted Properly
Bad Check Valve
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
Kidney Lift chatters or loses position
Defective or Dirty Check Valve
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
Lift Rods Binding
KIDNEY LIFT
CYLINER ASSEMBLY
UP CIRCUIT
DOWN
CIRCUIT
COPPER
LINES
PLUMBING
TERMINAL
CHECK
VALVE
SPEED
CONTROL
MINI-VALVE
INTERNAL OIL RETURN
TO RESERVOIR
INTERNAL OIL
FROM PUMP
Figure 3-7. Kidney Lift Circuit
Page 20
3-10. SLIDE DIAGNOSIS CHART
Problem
Slide function moves improperly
Reason
Incorrect Speed Adjustment
Spool Valve Not Centered or Adjusted Properly
Bad Check Valves
Low on Oil
Pinched Hose
Defective Mini-Valve
Pressure Relief Valve Not Set Properly
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
Slide function chatters or loses position
Defective or Dirty Check Valve
Oil Leakage in Circuit
Air Inside Cylinder
Pinched Hose
Low on Oil
SLIDE
CYLINDER ASSEMBLY
PISTON
PISTON
PLUMBING
TERMINAL
CHECK
VALVE
COPPER
LINES
SPEED
CONTROL
MINI-VALVE
INTERNAL OIL RETURN
TO RESERVOIR
INTERNAL OIL
FROM PUMP
Figure 3-8. Slide Circuit
Page 21
3-11. BRAKE CIRCUIT DIAGNOSIS CHART
Problem
Brakes will not set properly
NOTE
If brakes have been released with the
Emergency Brake Release Valve,
brakes will not reset until BRAKE UNLOCK Circuit has been activated.
Reason
Emergency Brake Release Valve Open or Defective
Spool Valve Not Centered or Adjusted Properly
Bad Check Valve
Low on Oil
Pressure Relief Valve Not Set Properly
Pinched Hose
Defective Mini-Valve
Defective Relay Box or Pendant Control
Brakes will not stay locked
Emergency Brake Release Valve Open or Defective
Defective or Dirty Check Valve
Oil Leakage in Circuit
Leaking "O" Ring Inside Cylinder
Brakes will not retract properly
Incorrect Speed Adjustment
Bad Check Valve
Spool Valve Not Centered
Defective Mini-Valve
Pinched Hose
Defective Solenoid or Wiring
Defective Relay Box or Pendant Control
BRAKE
CYLINDER
BRAKE
CYLINDER
PLUMBING
TERMINAL
CHECK
VALVE
MINI-VALVE
BRAKE
CYLINDER
SPEED
CONTROL
RETURN TO
RESERVOIR
EMERGENCY
BRAKE RELEASE
COPPER
LINE
BRAKE
CYLINDER
RELEASE LEVER
Figure 3-9. Brake System Circuit
Page 22
3-12. Flexible Hose Identification and Placement
The flexible hydraulic hoses used in the table are
number coded to aid in the correct placement of the
hoses from the plumbing terminal to their respective hydraulic cylinders. Figure 3-10 shows the
correct placement of the flexible hydraulic hoses
and their respective number codes.
Figure 3-10. Flexible Hoses
Page 23
3-13. Kidney Lift System
B
LEFT
CYLINDER
A
The Kidney Lift cylinders are connected in series
so that both cylinders operate simultaneously.
Hydraulic pressure on one side of the lead piston
causes the piston to move. The piston movement
forces the hydraulic fluid on the other side of the
piston through the system to the other cylinder.
This simultaneously activates the other piston. A
bypass system is connected to the right cylinder
assembly for initial set-up and adjustment of the
kidney lift system. Use the following procedures to
bleed or adjust the system if needed.
BYPASS VALVE
D
UP
Figure 3-12.
a. Bleeding the System - If the hydraulic lines or
cylinders have been disconnected from the kidney
lift system for any reason, use the following procedure to bleed the air from the system.
2. Make sure the bypass valve is closed (valve
screw tight) and activate "KIDNEY DOWN". The
hydraulic fluid will fill cavity "D" as shown in figure
3-11.
B
LEFT
CYLINDER
A
CLOSED
A
BYPASS VALVE
D
OPEN
C
RIGHT
CYLINDER
UP
Figure 3-13.
5. Repeat steps 3 and 4 as needed to remove
any remaining air in the system.
C
RIGHT
CYLINDER
DOWN
Figure 3-11.
3. Open the bypass valve by loosening the
screw in the bottom of the valve and activate
"KIDNEY UP". Hydraulic fluid fills cavity "A" and
pushes the piston into cavity "B". The open valve
allows a path for air to escape from cavity "B"
without affecting the piston in "C". See figure 3-12.
4. Leave the bypass valve open and activate
"KIDNEY DOWN". Hydraulic pressure keeps the
piston in chamber "C", the hydraulic fluid passes
through the bypass valve and fills cavity "B" pushing the piston into cavity "A". See figure 3-13.
Page 24
LEFT
CYLINDER
6. With both pistons in the full down position,
activate "KIDNEY DOWN" to apply full system
pressure and close the bypass valve (tighten the
screw).
BYPASS VALVE
D
C
RIGHT
CYLINDER
B
1. Remove the kidney lift top section and begin
the procedure with both pistons in the down position (chambers A & C) as shown in figure 3-11.
OPEN
b. Cylinder Adjustment - If either of the kidney lift
cylinders reaches the end of the down stroke
before the other one, an adjustment is needed. Use
the following procedure to adjust the system.
1. If the right side bottoms out before the left
side, open the bypass valve and activate "KIDNEY
DOWN" to align the cylinders.
2. If the left side bottoms out before the right
side, activate "KIDNEY UP" to raise the cylinders.
When the cylinders are at the full up position, open
the valve and activate "KIDNEY UP" to align the
cylinders. Close the valve before lowering the
cylinders.
3. When the adjustment is complete, make
sure the cylinders are completely down, activate
"KIDNEY DOWN" and tighten the valve.
Page 25
SECTION IV ELECTRICAL SYSTEM
4-1. General
4-2. Components
The complete electrical system (with the exception of the hand-held pendant control and the return
circuit micro-switches) is contained within the base
of the table. The pump motor and the hydraulic
valves are controlled electrically with the pendant
control.
Refer to figure 4-1 for the relationship of the electrical components.
The electrically operated functions are as follows:
- TRENDELENBURG - Head up and down
- LATERAL TILT - Right and left
- BACK SECTION - Up and Down
- ELEVATION - Up and Down
-TOP SLIDE
a. Wires, Connectors, Switches, Fuse - These
provide the path for the various electrical circuits.
b. Relay Box - Contains the step down transformer, full wave rectifier, and relay switches. The
relay switches are activated by the pendant control
and in turn energize the solenoid.
c. Hand-Held Pendant Control - Closes microswitches to activate relay box. Operates on 5
VDC.
d. Solenoids - These electrically open and
close the hydraulic ports of the mini-valve to direct
the fluid to the correct cylinders. They operate on
120 VAC.
- LEG SECTION - Up and Down
- FLEX / REFLEX
e. Motor/Pump Assembly - 120 VAC, 60 HZ,
200 Watt capacitor induction motor.
- KIDNEY LIFT - Up and down
4-3. Battery Model Components
- RETURN TO LEVEL
The functions of the battery model tables are the
same as the standard 120 VAC models. The
electrical components and operation however, vary
greatly between the two models. To simplify the
troubleshooting procedures, the battery model
tables are covered separately in Section VI.
- BRAKE UNLOCK - Brake release
The power requirements are 120 VAC, 60 Hz, fuse
protected. The main power on-off switch is an
enclosed DPST type and the power cord is a threewire, fifteen foot long, UL listed cord with a threeprong hospital grade plug.
Page 26
3500
Figure 4-1. 3500 Electrical Circuit Block Diagram
Page 27
3500
SECTION V ELECTRICAL SYSTEM TROUBLESHOOTING
5-1. Troubleshooting Notes
The basic operation of each component will be
defined along with a drawing and explanation on
how to check it out.
2. Disconnect connector CN4 from the relay
box. See figure 5-1. Leave all other connectors
connected.
Certain defective components could cause the
entire table to stop functioning or only one control
function to stop. It would depend on what part of the
component failed. Other defective components
would only cause one control function to stop.
The following defective components could cause
all control functions to be affected:
CN4
RELAY BOX
a. Motor/Pump Assembly (starting capacitor)
b. Main Switch Circuit and Wiring
The following defective components could cause
all control functions to be affected or only one
control function:
a. Relay Box
b. Pendant Control
The component listed below would only affect one
control function:
Solenoid
When troubleshooting an electrical circuit, start at
the problem and work back to the power source.
Figure 5-1. Main Power Test
CAUTION
Line voltage (120 VAC) will be measured in this test. Do not touch uninsulated connector pins or meter test leads.
3. Use an AC voltmeter capable of measuring
120 VAC and measure the voltage between pins
1 and 2 (black and white wires) located in connector CN4. See figure 5-2. You should receive line
voltage 120 VAC.
5-2. Main Switch
The main power supply, 120 VAC, 60 HZ, comes in
through the power cord and through the main
switch. The main switch opens both lines when in
the "OFF" position. Two 10 amp fuses are used to
protect the complete electrical system and are
located next to the main switch.
ACV
a. Main Switch Test
4
The following test will determine if line voltage is
applied to connector CN4, which in turn would
power the table.
PIN NO.
COLOR
1
2
3
4
5
White
Black
Red
Blue
Yellow
1. Plug the power cord into the 120VAC power
supply (wall receptacle) and turn ON the main
switch.
Page 28
5
3
2
1
Figure 5-2. Connector CN4
3500
b. Test Results
a. Pendant Control Test
If you do not receive the correct voltage measurement, the problem would have to be in the wires,
main switch, fuses, or power cord. If the correct
voltage is obtained, everything is good up to this
point and the problem would have to be in another
area.
The following test will determine if the micro-switches
inside the Pendant Control are function-ing correctly.
1. Unplug the pendant control from the base of
the table. You will be checking the cord side
connector.
5-3. Pendant Control
The Pendant Control consists of 18 micro-switches
(buttons). When any of the circuits are completed
(by depressing a control button) the appropriate
relay contacts (located in the relay box) close
applying 120V potential to the appropriate solenoid
to operate the mini-valve and the pump/motor. The
Pendant Control has only 5-6 volts applied to it.
2. Use an ohmmeter R x 1 scale and check the
continuity between pin 1 and pins 4 through 24.
See figure 5-3.
3. Ohmmeter must show continuity between
the pins that are indicated when the appropriate
buttons are pressed.
Figure 5-3. Pendant Control Test
Page 29
3500
NOTE
Pins 2 and 3 are connected to the green
LED (power ON light on the pendant
control) and pin 20 is connected to the
amber LED (slide center light on the
pendant control) these pins cannot be
checked with an ohmmeter.
b. Test Results:
If you do not receive continuity between any of the
pins, either the micro-switch in the Pendant Control
is defective or a wire is broken. Either of these
problems can be repaired easily.
d. Test Results:
If you do not receive the correct voltage reading,
the wiring or connector pins may be faulty. Disconnect connector CN8 from the relay box and using
an ohmmeter, test the continuity between the corresponding pins in connectors CN8 and the table
base connector. See figure 5-5. If the correct
readings are obtained, this part of the circuit is
okay.
BASE
CONNECTOR
BASE
CONN.
If you receive correct readings with the meter, the
Pendant Control is okay.
CN8
c. Wiring Harness Test
The following test checks the wires leading from
the relay box connector CN8 to the 24 pin connector table socket. These wires apply low voltage to
the pendant control buttons.
1. The power cord should be plugged into the
wall socket and the main switch turned ON.
A1
A13
B1
B13
2. Disconnect the pendant control from the
base connector. All other connectors should be
connected.
3. Use a DC voltmeter 10V scale and measure
the following pins located in the 24 pin table base
connector. See figure 5-4.
NOTE
Pin 19 in table base connector will have
no voltage potential unless 1 of the
return-to-level micro-switches are activated, i.e. trendelenburg, tilt, etc.
+ TEST
LEAD
- TEST
LEAD
DC
VOLTS
1
1
2, 3, 21, 22
4 - 20, 23, 24
0
5-6
Figure 5-4. Table Base Connector
Page 30
COLOR
CN8
Red/White
White
Black
Red
White/Red
Yellow
Brown
White/Brown
Blue/Whte
Orange
White/Orange
Gray
White/Gray
White/Yellow
Purple/White
Black/White
Purple
White/Purple
Blue/Yellow
Blue/Red
A1
B1
A2
B2
A3
B3
A4
B4
A5
B5
A6
B6
A7
B7
A8
B8
A9
B9
A10
B10
A11
B11
A12
B12
A13
B13
OHM
CN8
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
Blue
White/Blue
Figure 5-5. Base Connector Continuity Test
5-4. Relay Box
The 120 volt power supply is directly connected to
the relay contacts. When these contacts are
closed, 120 volts is supplied to the solenoids which
are mounted on the hydraulic mini-valves. One
relay is used to supply 120V to the pump/motor and
is always activated no matter what control function
is selected. The brake locking circuit relay is also
activated when any control function other than
BRAKE UNLOCK is initially selected.
Also, inside the relay box is a step-down transformer and full-wave rectifier which decreases the
line voltage to 5.5 volts. This low voltage potential
controls the relays by the use of the hand-held
pendant control buttons. Basically the relays enable a 5.5 volt potential to control the 120 volt circuit.
The following tests will determine if the relay box is
functioning correctly.
3500
a. Relay Box Input Connector CN4
d. Test Results:
1. Plug the power cord into the 120 VAC power
supply (wall receptacle) and turn the main switch
ON. Leave all connectors connected.
If you do not receive the correct meter readings, the
relay box or wiring is defective. If the correct
readings are obtained, this part of the relay box is
okay. Proceed to the next step.
CAUTION
Line voltage (120 VAC) will be measured in this test. Do not touch uninsulated connector pins or meter test leads.
e. Relay Box Output Connectors CN6, CN7A
& CN7B
2. Use an AC voltmeter capable of measuring
120 volts and measure the voltage between pins 1
(white) and 2 (black) of connector CN4 for input
voltage. See figure 5-6. Meter should read line
voltage 120 VAC.
3. Activate any table function with the Pendant
Control and using an AC voltmeter, test the voltage
at pins 3 and 4 of CN4 for output to the pump. Meter
should read 120 VAC.
4
PIN NO.
COLOR
1
2
3
4
5
White
Black
Red
Blue
Yellow
1
ACV
2
3
5
Figure 5-6. Connector CN4
b. Test Results:
This test checks the high voltage (120V) that is
used to energize the solenoids.
CAUTION
120 VAC will be measured in this test.
Do not touch uninsulated connector
pins or meter test leads.
1. The power cord should be plugged into the
wall receptacle and main switch turned ON.
2. Disconnect the motor connector CN15. All
other connectors should be connected. Test connectors CN6, CN7A and CN7B from the back while
attached to the relay box.
3. Activate each of the Pendant Control buttons
and using an AC voltmeter capable of measuring
120VAC, measure the voltage between the appropriate connector pins located in connector CN6,
CN7A or CN7B. See figure 5-7. Polarity of meter
test leads is not important. Meter should read
120VAC.
If you do not receive the correct meter readings, the
relay box or wiring is defective. If the correct
readings are obtained, this part of the relay box is
okay. Proceed to the next step.
c. Relay Box Output Connector CN8
ACV
1
CN6, CN7A OR CN7B
16
CN7A
CN6
This test checks the low voltage applied to the pendant control buttons.
1. The power cord should be plugged into the
wall receptacle and main switch turned ON.
2. Disconnect Pendant Control connector. All
other connectors should be connected.
3. Using a DC voltmeter, measure the voltage
between pin 1(+) and pins 4 through 24 (-) of the
table base connector. See figure 5-4. Meter should
read 5-6 volts.
FUNCTION
PINS
FUNCTION
PINS
Table Up
Table Down
Rev Trend
Trend
Back Up
Back Down
Tilt Right
Tilt Left
1-2
3-4
5-6
7-8
9 - 10
11 - 12
13 - 14
15 - 16
Leg Up
Leg Down
Kidney Up
Kidney Down
Brake Set
Brake Unlock
Flex
Reflex
1-2
3-4
5-6
7-8
9 - 10
11 - 12
13 - 14
15 - 16
CN7B
Slide Head
Slide Foot
1-2
3-4
Figure 5-7. Relay Box Output Connectors
CN6 and CN7
Page 31
3500
f. Test Results:
b. Step #1
If you do not receive the correct meter readings, the
relay box or wiring is defective and should be
replaced.
NOTE
1. Plug the table cord into the wall receptacle
and turn main switch ON.
Before deciding the relay box is defective, check the wires and pins in the
connector blocks to make sure they are
not loose or making a bad connection
with their mate.
2. Disconnect the 2 pin connector from the
solenoid in question. See figure 5-8.
3. Use a voltmeter capable of measuring 120
VAC and measure the voltage across the 2 pin
connector. Polarity of meter leads is not important.
NOTE
5-5. Solenoids
The solenoids are energized by 120 volt potential
that is controlled by the relays located inside the
relay box.
The solenoid windings are protected from excessive heat with an internal thermal fuse that will open
after approximately seven (7) minutes of continuous operation. The solenoid must be replaced if the
internal thermal fuse has been blown. The solenoids are mounted directly on either side of the
hydraulic mini-valves and push the spool valve in
one direction or the other depending upon which
solenoid is activated.
The appropriate pendant control button must be pushed during this test.
The motor will run when this test is
performed, and the brake locking solenoid will be activated by any function
other than UNLOCK if brakes are not
set.
c. Test Results:
If you do not receive the correct voltage, the problem could be in the wires leading to connectors
CN6, CN7A and CN7B. The problem could also be
in the relay box or the Pendant Control (refer to
appropriate section for troubleshooting).
a. Solenoid Test
The following tests check the voltage applied to the
solenoids and the resistance of the solenoid coil.
NOTE
If a solenoid does not function when the
pendant control button is pushed, the
problem could be the pendant control,
the relay box, or the solenoid.
NOTE
Each solenoid is controlled with 120V
source coming from the relay box. This
source can easily be checked by measuring the voltage at the 2 pin connector
in question.
CAUTION
Line voltage will be measured in this
test. Do not touch uninsulated connector pins or meter test leads.
Page 32
If the correct voltage is obtained, everything is good
up to that point and the problem is more than likely
the solenoid.
d. Step #2
The solenoid can be checked out using an ohmmeter R x 1 scale.
1. Measure the resistance between the two
pins of the connector in question. See figure 5-8.
Connector being tested must be disconnected.
Polarity of meter leads is not important.
2. The meter should read approximately 80-90
ohms at room temperature (58 ohms for tables S.N.
1997-4&L).
3. Measure the resistance between either pin
and solenoid housing.
4. Meter should read infinity.
3500
e. Test Results:
5-6. Motor/Pump Assembly
If the solenoid does not check out with the meter,
it is more than likely defective and must be replaced.
The electric motor is a capacitor start type with a
rating of 120 VAC, 200 watts. The field windings
are protected with a thermal protector that will open
the winding circuit if the motor is run continuously
for approximately 10 minutes. This protector will
take about 10 minutes to automatically reset. The
oil pump unit is attached to the bottom of the motor
and is a gear type displacement pump with a
pumping capacity of .4 liter per min. The Motor/
Pump Assembly is mounted on an insulated motor
plate in the base of the table. The starting capacitor
is mounted along side the motor/pump assembly.
NOTE
Whenever there are several components of the same type, a defective unit
can also be detected by substituting a
known good unit or wire connector. In
some cases this may be faster than
using a multi-meter.
Figure 5-8. Solenoid Test
Page 33
3500
a. Motor/Pump Test
c. Test Results:
The following tests will check the voltage applied to
the motor and the resistance of the motor field
windings.
If you do not receive the correct meter readings, the
problem could be in the wires, connectors, relay
box, or main switch (refer to appropriate section for
troubleshooting).
CAUTION
Line voltage will be measured in this
test. Do not touch uninsulated connector pins or meter test leads.
If the correct voltage is obtained, everything is good
up to that point and the problem could be either the
motor or the starting capacitor.
d. Step #2
b. Step #1
1. Plug the power cord into 120 VAC power
supply (wall receptacle). Turn main switch ON.
2. Disconnect the 3 pin connector CN15 at the
motor. Leave all other connectors connected. See
figure 5-9.
If the starting capacitor is shorted or grounded, the
motor will not run. Capacitors very seldom fail, and
it requires a dielectric tester to accurately test one.
However, an ohmmeter can be used to determine
if the capacitor will store a low voltage charge and
most of the time this is adequate.
1. Turn the main switch OFF.
PUMP/MOTOR
ASSEMBLY
2. Connector CN15 should be disconnected.
3. Use the R x 100 scale of the ohmmeter and
touch pins 2 and 3 of connector CN15. See figure
5-10.
CN15
CAPACITOR
e. Test Results:
Figure 5-9.
3. Use a voltmeter capable of measuring 120
VAC and measure the following connector pins in
connector CN15. See figure 5-10.
The meter needle should move up scale and then
back down to infinity. This would indicate that the
capacitor is storing an electrical charge.
NOTE
The capacitor may have to be discharged first (by shorting pins 2 and 3
together) before you will be able to see
the ohmmeter needle swing up the scale.
ACV
3
2
1
PIN NO
AC VOLTS
1-2
1-3
2-3
120
120
0
f. Step #3
The motor windings can be statically checked for
resistance using an ohmmeter.
1. Turn main power switch OFF.
2. Connector CN15 should be disconnected.
Figure 5-10. Connector CN15
Page 34
3500
3. Use the R x 1 scale of the ohmmeter and
measure the resistance between the pins located
in the pump connector CN15. See figure 5-11.
OHM
PIN NO
METER
1-2
1-3
2-3
Approx. 5 ohms
Approx. 4 ohms
Approx. 8 ohms
Figure 5-11. Pump Connector CN15
g. Test Results:
If you do not receive the correct meter readings, the
motor or wiring is defective.
5-7. Return-to-Level Micro-Switches.
The return-to-level feature is activated by a single
button on the pendant control and automatically
levels the major table functions, lateral tilt, trendelenburg, flex, back section, and leg section.
NS-6
CS-3
NS-7
CS-2
The kidney lift has a back section-up inhibit switch
to prevent the table back section from damaging
the kidney lift when the lift is raised. The back
section still has the capability to be lowered and
raised, but will not raise more than 45° above
horizontal until the kidney lift is completely down. If
the back section is raised more than 45° above
horizontal, the system will not allow the kidney lift to
be raised.
The slide function has inhibit switches to prevent
damage to the back and leg sections. If the back
section is below horizontal the top will not slide
toward the foot end. If the leg section is lowered
more than 45° below horizontal the top will not slide
toward the head end. Likewise, if the top is slid
toward the foot end, the back section will not go
below horizontal. If the top is slid toward the head
end, the leg section will not go more than 45° below
horizontal.
The return-to-level/inhibit system consists of 12
micro-switches, an electrical connector, 2 terminal
strips and the related wiring. The micro-switches
are mounted on or adjacent to the function they
control and are wired for normally open or normally
closed operation. The micro-switches are cam or
lever actuated and can be adjusted at the individual
switch mounting brackets. See figure 5-12.
CS-1
CS-5
NS-1
NS-4
NS-3
NS-2
NS-5
CS-4
RELAY BOX
NS-1
NS-2
NS-3
NS-4
NS-5
NS-6
NS-7
TREND
REV. TREND
TILT LEFT
TILT RIGHT
BACK - DOWN TO LEVEL / SLIDE INHIBIT
BACK - UP TO LEVEL
LEG - DOWN TO LEVEL
CS-1
CS-2
CS-3
CS-4
CS-5
SLIDE/LEG DOWN INHIBIT
SLIDE/BACK DOWN INHIBIT
KIDNEY/BACK 45˚ UP INHIBIT
LEG DOWN 45˚/SLIDE INHIBIT
BACK UP 45˚/KIDNEY UP INHIBIT
CN2
Figure 5-12.
Page 35
3500
The micro-switches operate on low voltage, and
control the function circuits (pump/motor and appropriate solenoid valves) when activated by the
pendant control RETURN button.
cover on the top of the elevation column. Connector
CN2 plugs into the relay box and is the most
convenient location to make circuit continuity
checks. See fig. 5-13 for connector pin locations.
The micro-switches are wired to the relay box
through 2 terminal strips, a riser cord and the 15 pin
connector CN2. See figure 5-12 for switch location
and identification.
a. Switch Test
5-8. Return/Inhibit System Troubleshooting
If a problem is suspected in the return circuits,
disconnect the connector CN2 from the Relay Box
to eliminate the circuits. Ensure that all table
functions operate properly using the Pendant Control. If the functions do not work properly using the
Pendant Control, refer to the appropriate test section and make all needed repairs before working on
the return circuits.
Turn Main Power ON, lock the table brakes, and
place the table top sections in a level position with
the Kidney Lift down. Disconnect connector CN2
from the relay box and using an ohmmeter, test the
wiring and switch operation at the appropriate pin
numbers for the micro-switch in question as shown
in figures 5-14 through 5-21.
NOTE
Be sure to isolate the circuit when making continuity checks.
NOTE
NOTE
It is normal for the back section to move
up if the RETURN button is pushed
when connector CN2 is disconnected
from the relay box.
All of the micro-switches are connected to the relay
box via a wiring harness and the micro-switch riser
cord from terminal strips 1 and 2 to connector CN2.
The terminal strips are located under the hose
Page 36
If you do not receive the proper continuity results at connector CN2 it does not
necessarily mean the micro-switch is
defective. There could be a problem
with the riser cord between connector
CN2 and terminal strips 1 and 2, or in
the wiring from the switch to the terminal
strips. Further tests will have to be
made to determine the exact problem.
Figure 5-13. Return / Inhibit Micro-Switch Test
3500
1
WHITE
NC
5
LIGHT BLUE
NO
2
BLUE
NS-1
1
COM
14
2
COM
CN-2
NO
NS-1. Trendelenburg
Test at pins 1 & 14
NS-2
NC
TS-1
NS-2. Reverse Trendelenburg
Test at pins 2 & 14
Table
Position
Switch
Position
Meter
Reading
Table
Position
Switch
Position
Meter
Reading
Level
Head Up
Head Dn
Open
Open
Closed
Infinity
Infinity
0
Level
Head Up
Head Dn
Open
Closed
Open
Infinity
0
Infinity
When table is in Trendelenburg Position,
NS-1 brings the top back to level.
When table is in Reverse Trendelenburg
Position, NS-2 brings the top back to
level.
Figure 5-14. Trendelenburg Return Switches
NS-3. Lateral Tilt-Left
Test at pins 3 & 14
NS-4. Lateral Tilt-Right
Test at pins 4 & 14
Table
Position
Switch
Position
Meter
Reading
Table
Position
Switch
Position
Meter
Reading
Level
Tilt Right
Tilt Left
Open
Open
Closed
Infinity
Infinity
0
Level
Tilt Right
Tilt Left
Open
Closed
Open
Infinity
0
Infinity
When table is inTilt-Left Position, NS-3
brings the top back to level.
When table is in Tilt-Right Position, NS-4
brings the top back to level.
Figure 5-15. Lateral Tilt Return Switches
Page 37
3500
NS-6
7
6
NO
RED/WHITE
COM
PINK
13
8
TS-1
13
8
PINK
RED
5
6
TS-1
CN-2
NO
COM
NS-5
NOTE
When CN-2 is disconnected, BACKDOWN function will not operate.
NS-5. Back Section Down
Test at pins 5 & 13
NS-6. Back Section Up
Test at pins 6 & 13
Table
Position
Switch
Position
Meter
Reading
Table
Position
Switch
Position
Meter
Reading
Level
Back Dn
Back Up
Closed
Open
Closed
0
Infinity
0
Level
Back Dn
Back Up
Open
Open
Closed
Infinity
Infinity
0
When the Back Section is Down, NS-5
brings the Back Section Up to level and
will not allow Top Slide toward foot.
When the Back Section is Up, NS-6
brings the Back Section Down to level.
Figure 5-16. Back Section Return Switches
NS-7
1
BROWN
7
13
CN-2
8
PINK
NC
NO
TS-2
NS-7. Leg Section Down
Test at pins 7 & 13
Table
Position
Switch
Position
Meter
Reading
Level
Leg Dn
Open
Closed
Infinity
0
When the Leg Section is Down, NS-7
brings the Leg Section Up to level.
Figure 5-17. Leg Section Return Switch
Page 38
COM
3500
NOTES
SLIDE function will not operate when
CN-2 is disconnected.
3
9
4
10
13
7
CN-2
TS-2
BLACK
BLACK/WHITE
PINK
NC
COM
CS-2
CS-1. Leg Down 45˚ Inhibit
Test at pins 9 & 13
NC
COM
CS-1
CS-2. Back Down Inhibit
Test at pins 10 & 13
Table
Position
Switch
Position
Meter
Reading
Table
Position
Switch
Position
Meter
Reading
Center
Slide Hd
Slide Ft
Closed
Closed
Open
0
0
Infinity
Center
Slide Hd
Slide Ft
Open
Closed
Open
Infinity
0
Infinity
When Top is slid toward head, CS-1 will
not allow Leg Section to go more than
45˚ below horizontal.
When Top is slid toward foot, CS-2 will
not allow Back Section to go below
horizontal.
Figure 5-18. Leg Down / Back Down Inhibit Switches
CS-3. Back Up Inhibit Switch
Test at pins 11 & 13
Table
Position
Switch
Position
Meter
Reading
K-Lift Dn
K-Lift Up
Open
Closed
Infinity
0
When K-Lift is Up, CS-3 will not allow
Back Section to go more than 45° above
horizontal.
Figure 5-19. Back Up Inhibit Switch
Page 39
3500
CS-4. Slide Inhibit
Test at pins 8 & 13
Table
Position
Switch
Position
Meter
Reading
Level
Leg Dn
Open
Closed
Infinity
0
more than 45°
When Leg Section is more than 45°
below horizontal, CS-4 will not allow Top
to Slide toward head.
Figure 5-20. Slide to Head Inhibit Switch
CS-5. Slide Inhibit
Test at pins 12 & 13
Table
Position
Switch
Position
Meter
Reading
Back Up Less Than 45°
Back Up More Than 45°
Open
Closed
Infinity
0
When Back Section is more than 45° above horizontal, CS-5 will not allow Kidney Lift to operate.
Figure 5-21. Kidney Lift Inhibit Switch
Page 40
3500
b. Switch Adjustment.
If proper readings are not obtained during test or if
table does not properly return to level, use the
following procedure to adjust the switches.
1. Apply table brakes and (using a level) level
the table top using the TRENDELENBURG and
LATERAL-TILT function buttons on the pendant
control.
2. For all switches except the Leg Section
switches, carefully loosen the switch retaining
screws, and adjust the switches as needed. See
figure 5-22.
RETAINING
SCREWS
3. To adjust the Leg Section switches remove
seat section top, loosen the two Phillips head
screws securing the bracket, adjust the switch,
tighten screws and replace seat section top. See
figure 5-23.
PHILLIPS HEAD
SCREWS
LEG SECTION
MICRO-SWITCH
BRACKETS
Figure 5-23. Leg Section Micro-Switch
Adjustment.
MICRO-SWITCH
Figure 5-22. Micro-Switch Adjustment
Page 41
3500B
SECTION VI -3500B- BATTERY MODEL, ELECTRICAL TROUBLESHOOTING
6-1. General
6-3. Main Switch
The battery table components operate on 24VDC.
The internal charging system also incorporates the
components to transform the 120VAC input to
24VDC output to the components.
The main power supply, 120 VAC, 60 HZ, comes
in through the power cord and through the main
switch. The main switch opens both lines when
in the "OFF" position. Two 10 amp fuses are used
to protect the complete electrical system and are
located next to the main switch.
6-2. Troubleshooting Notes
The basic operation of each component will be
defined along with a drawing and explanation on
how to check it out.
Certain defective components could cause the
entire table to stop functioning or only one control
function to stop. It would depend on what part of the
component failed. Other defective components
would only cause one control function to stop.
The following defective components could cause
all control functions to be affected:
a. Motor/Pump Assembly
b. Main Switch Circuit and Wiring
The following defective components could cause
all control functions to be affected or only one
control function:
a. Relay Box
b. Pendant Control
The component listed below would only affect one
control function:
Solenoid
a. Main Switch Test
The following test will determine if line voltage is
applied to connector CN12, which in turn would
supply 120VAC power to the table.
1. Plug the power cord into the 120VAC supply
(wall receptacle) and turn the main switch ON.
2. Disconnect connector CN12. See figure
6-2. Leave all other connectors connected.
CAUTION
Line voltage (120 VAC) will be measured in this test. Do not touch uninsulated connector pins or meter test leads.
3. Use an AC voltmeter capable of measuring
120 VAC and measure the voltage between pins 1
and 2 (black and white wires) located in connector
CN12. See figure 6-1. You should receive line
voltage 120 VAC.
BLACK
(2)
When troubleshooting an electrical circuit, start at
the problem and work back to the power source.
NOTE
On the battery model tables, troubleshooting should begin by switching the operating
mode. For example; if a function fails when
attemptingtooperatethetableintheAC120V
mode, switch to the BATTERY mode. If the
function now operates, the problem is probably located between the power cord and
the relay box. If the function also fails when
in battery operation, use the auxiliary
switches to operate the function. If the
function now operates, the problem is probably in the pendant control, connectors or
wiring from the pendant control to the relay
box. All connector pins are numbered
usually with very small numbers.
Page 42
ACV
WHITE
(1)
Figure 6-1. Connector CN12 Test
b. Test Results
If the correct voltage is obtained, everything is
good up to this point and the problem would have
to be in another area.
If you do not receive the correct measurements,
the problem would have to be in the wires, main
switch, fuses, or power cord.
3500B
SOLENOID
COIL 24VDC
PENDANT
CONTROL
MINI-VALVES
AUXILIARY
CONNECTOR
CN14
CN13
CN3
CN7
TS1
CN1
TO
RETURN
CIRCUIT
CN8
RELAY BOX
AUXILIARY
SWITCHES
TS2
CN2A
CN10
CN2B
CHARGER BOX
CAPACITOR
BATTERIES
CN4
PUMP
SWITCH-OVER
RELAY
CN16
CN15
22 VAC FROM
TRANSFORMER
120 VAC TO
TRANSFORMER
CN51
CHARGER
BOX
CN14
POWER
CORD
FUSE
15AMP
CN12
CN13
MAIN
POWER
SWITCH
ICN1
FUSE
10AMP
BATTERY CHARGE
INDICATOR
Figure 6-2. Electrical Circuit Block Diagram, Model 3500B
Page 43
3500B
Check the continuity from the power cord connector ICN1, through the fuses, switch and wiring to
connector CN12. Remove the power cord, disconnect CN12 (black and white wires), and test as
shown in figure 6-3.
4. Continue to press the TABLE UP button on
the pendant control so that the pump motor continues to run and using a DC voltmeter, check the
voltage drop of each battery individually. See figure
6-4.
5. Meter should read 12VDC ± 1VDC.
BLACK
TO GROUND
CN12
2
ICN1
WHITE
1
BATT 1
BATT 1
N
L
OHM
DCV
Figure 6-3. CN12 to ICN1 Continuity Test
Figure 6-4.
6-4. Batteries
b. Test Results
The BATTERY operating mode is powered by two
12 volt batteries connected in series to provide the
24 volt operating power.
A reading of 11 volts or below indicates the battery
needs charging.
The battery system voltage should be 24VDC at a
range of 22VDC to 26VDC. If the battery charge
level falls below 23.5 volts the BATTERY operation
indicator on the pendant control will blink indicating
that the batteries require recharging. The built-in
charging system automatically keeps the batteries
at the proper charge level when the AC120V operating mode is ON. The charging system will
operate while the table is being operated in the
AC120V mode.
After batteries have been fully charged, repeat the
full load test. If either battery's voltage drops below
11VDC it should be replaced.
6-5. Battery Charging Box/AC120V
Transformer
The Battery Charging Box contains the battery
charging system as well as the components for
AC120V operation (except the transformer).
a. Battery System Test
a. Transformer Test
1. Disconnect the main power cord and using
a DC voltmeter, test each individual battery at its
terminals. Meter should read 12VDC ± 1V.
1. Confirm 120VAC input at CN12 using Main
Switch test in 6-3a.
2. To accurately test the batteries, they must
be tested under a full load. Disconnect the main
power cord and make sure all other connectors are
connected.
3. Turn BATTERY power ON and elevate the
table to its full up position.
Page 44
2. Connect CN12, disconnect CN13 (brown
and red wires) and using an AC voltmeter, test the
transformer output at CN13. See figure 6-5.
3. Meter should read 22VAC.
3500B
BROWN
(2)
d. Test Results
RED
(1)
ACV
Figure 6-5. Connector CN13 Test
b. Test Results
If the correct voltage is obtained, everything is
good up to this point and the problem would have
to be in another area.
If you do not receive the correct measurements,
the problem may be in the wires, connectors, or
transformer. The transformer is located in the rear
of the base under the stainless steel base cover.
The stainless steel cover will have to be disconnected and lifted from the base for access to the
transformer for further testing.
If you do not receive the correct readings, the
charger system, connectors, wires, or the transformer may be defective.
e. Charging System Output Adjustment
If output reading at pins 3 and 4 is not 26.5 ± 1VDC,
the output can be adjusted at the variable resistor
VR-51 on the circuit board inside the Charging Box.
See figure 6-7. Turn the adjuster clockwise to
decrease the voltage. Counterclockwise to increase the voltage.
NOTE
The battery connectors must be disconnected to adjust the battery charger
output.
c. Battery Charging Box Test
1. Make sure all connectors are connected and
turn AC120V operation ON. Using a DC voltmeter,
test pin 3(+) and pin 4(-) of CN51. DO NOT
disconnect connector CN51. See figure 6-6.
VR51
RED
(3)
(5) RED / WHITE
CN51
5 3
1
Figure 6-7
(6) BLUE / WHITE
BLACK
(4)
DCV
(2) BROWN
(1) BROWN
Figure 6-6. Connector CN51
2. Meter should read 26.5 ±1VDC.
3. Test pin 5(+) and pin 6(-) of CN51 with DC
voltmeter to test operation of CHARGING indicator
light (next to power cord connector).
4. Meter should read 26.5 ±1VDC if charger is
operating. If batteries are fully charged there will be
under 5 volts at pins 5 and 6.
Page 45
3500B
6-6. Switch-Over Relay
NOTE
The battery charging circuit is only
operational when the table is in the
AC120V operating mode.
a. Switch-Over Relay in OFF Position
The Switch-Over Relay supplies the 24 volt
input power from either the BATTERY or
AC120V operating modes to the relay box for
table operation. In the normal OFF position,
BATTERY power is supplied to the relay box.
See figure 6-8.
RELAY BOX
CN4
(-)
S-O RELAY
FUSE
15A
7
2
1
8
3
4
6
5
c. Switch-Over Relay Test
Using a DC voltmeter, test the operation of the
relay in both the OFF (AC120V - OFF) and
Activated (AC120V - ON) positions. See figure
6-10.
NOTE
The Switch-Over Relay mounting
block may have to be removed from
the base for test access.
OFF: (AC120V - OFF)
term. 7(-) and term. 1(+) = 24 to 28VDC
term. 7(-) and term. 6(+) = 0VDC
Activated: (AC120V - ON)
term. 7(-) and term. 6(+) = 26.5±1VDC
BATTERY (+)
Figure 6-8. Relay in OFF Position
b. Switch-Over Relay in Activated Position
When the AC120V mode is activated by the main
switch, a signal from the relay box activates the
Switch-Over Relay. The relay then supplies the
AC operating mode output power to the relay box
and also activates the battery charging circuit. See
figure 6-9.
RELAY BOX
CN4
(-)
RELAY BOX
SIGNAL OUT
2
7
1 8
3 6
4 5
CAPACITOR
BATTERY (+)
CN14
CN51
CHARGING
BOX
Figure 6-9. Relay in Activated Position
Page 46
DCV
8
1
3
4
7
6
5
Figure 6-10. Switch-Over Relay
S-O RELAY
FUSE
15A
2
3500B
6-7. Pendant Control
b. Test Results
The Pendant Control is part of the solid state, multiplex, logic control system. The pendant control
contains illuminated, circuit board mounted switches
and a micro processor. The encoded output from the
pendant control is serial bit stream logic.
The output signal is transmitted to the micro processors in the relay box where the logic is decoded and
the appropriate relays for the selected function are
activated.
Pendant Control troubleshooting should begin by
switching the operating mode of the table. For
example; if a function fails when attempting to operate
the table in the AC120V mode, switch to the BATTERY mode. If the function now operates, the
problem is not the pendant control and probably is a
problem located between the power cord and the
relay box. If the function also fails when in battery
operation, use the auxiliary switches to operate the
function. If the function now operates, the problem is
probably in the pendant control, connectors or wiring
from the pendant control to the relay box.
If you do not receive the correct readings, the
wiring or connector pins may be faulty.
c. Base Connector Test
If correct readings are received, test the wiring from
the base connector to connector CN7 at the Relay
Box. Disconnect connector CN7 from the Relay
Box and using an ohmmeter, test the continuity
between the corresponding pins in connectors
CN7 and the base connector. See figure 6-12.
OHM
1
3
2
4
6
5
7
a. Pendant Control Test
There are no servicable components within the Pendant Control. The cord is detachable and can be
tested for continuity between the pins on the connectors. Use the following procedure to test the pendant
control cord.
Disconnect the cord from the base connector and
from the pendant control connector and using an
ohmmeter, test the continuity between the corresponding pins in the connectors. See figure 6-11.
BASE
CONNECTOR
1
2
3
4
5
6
7
CN7
Figure 6-12. Base Connector Continuity Test
If the correct readings are obtained, this part of
the circuit is okay and the problem may be
Pendant Control or the Relay Box. Contact
SKYTRON if all tests performed indicate that the
problem is located in the Pendant Control.
OHM
RED 1
2 BROWN
A
H
G
4 ORANGE
BLUE 3
5 BLACK
B
F
C
WHITE 6
Base Conn.
Pin
1
2
3
4
D
7 GREEN
Test Leads
Pend. Conn.
Base Conn.
Pin
Pin
A
B
C
D
5
6
7
E
Pend. Conn.
Pin
E
F
G
Figure 6-11. Pendant Control Cord Test
Page 47
3500B
6-8. Auxiliary Switches
The following tests will determine if the auxiliary
switches are functioning properly.
a. Switch Test
OHM
Figure 6-14. Auxiliary Switch Test
Disconnect connector CN3 at the Relay Box and
using an ohmmeter check for continuity at the
connector pins (pin 1A common) while activating
the appropriate switch. See figure 6-13. Meter
should read 0 ohms.
b. Test Results
If proper meter readings are not received, test the
individual switches as necessary. Using an ohmmeter, test the operation of an individual switch with
the (+) test lead at the center terminal of the switch
and the (-) test lead at the terminal opposite the
direction of the switch actuation. See figure 6-14.
Meter should read 0 ohms. If the switches check
out, the problem would have to be in the wires or
connector CN3.
6-9. Relay Box
The power supply is directly connected to the relay
contacts. When these contacts are closed, 24
volts is supplied to the solenoids which are mounted
on the hydraulic mini-valves. One relay is used to
supply power to the pump/motor and is always
activated no matter what control function is selected. The brake locking circuit relay is also
activated when any control function other than
BRAKE UNLOCK is initially selected.
Also, inside the 3500B relay box is a step-down
transformer and full-wave rectifier which decreases
the voltage to 5-6 volts. This low voltage potential
controls the relays by the use of the hand-held
pendant control buttons. Basically the relays enable a 5-6 volt potential to control the 24 volt circuit.
The following tests will determine if the relay box is
functioning correctly.
B8/B2 B8/A3 B8/A4 B8/A1 B8/A7 B8/B6
CN3
1
2
3
4
5
6
7
8
SW1
TABLE UP
B8/A2 B8/B3 B8/B4 B8/B1 B8/B7 B8/A6
TABLE DOWN
HEAD DOWN
SW2
HEAD UP
OHM
15 (A8)
RIGHT DOWN
LEFT DOWN
SW3
16 (B8)
1 (A1)
BACK UP
BACK DOWN
SW4
9
2 (B1)
CN8
10
11
12
13
14
15
16
Page 48
PIN NO
KIDNEY DOWN
KIDNEY UP
SW5
LEG UP
COLOR
PIN NO
COLOR
--
1 (A1)
Red
9 (A5)
2 (B1)
White/Red
10 (B5)
--
3 (A2)
Brown
11 (A6)
White/Purple
LEG DOWN
4 (B2)
Yellow
12 (B6)
Purple
PUMP MOTOR
5 (A3)
Orange
13 (A7)
Grey
6 (B3)
White/Orange
14 (B7)
White/Grey
7 (A4)
White/Brown
15 (A8)
Red/White
8 (B4)
Blue/White
16 (B8)
Pink
+24V
SW6
Figure 6-13. Auxiliary Switch Connector CN3
3500B
a. Checking Relay Box Input Power
d. Checking Output to Solenoids
1. Connect power cord to table. Plug the power
cord into the 120VAC supply (wall receptacle).
Disconnect connector CN4, leave all other connectors connected.
2. Using a DC voltmeter, test input power for
both the BATTERY and AC120V operating modes.
See figure 6-15. Meter should read approximately
24 -28 volts.
This test checks the voltage that is used to
energize the solenoids.
BATTERY mode
(Main Power OFF)
pin1=(+)
pin2=(-)
AC120V mode
(Main Power ON)
pin 5=(+)
pin 6=(-)
Connector CN4 Color Code
Pin 1 Red
Pin 5 White
Pin 2 Blue
Pin 6 Black
Pin 3 Yellow
Pin 7 Yellow
Pin 4 Blue
7
6
5
DCV
4
3
2
1
1. Activate either BATTERY or AC120V operating mode.
NOTE
•The Brake Lock function is activated
by pressing any function button (except
BRAKE UNLOCK). A timer in the Relay Box allows continuous output for
about 7 seconds. If the brakes are
already locked, no output is provided.
•The BRAKE UNLOCK button activates
another timer in the relay box which
allows continuous output for the brake
release function for approximately 7
seconds. If the brakes are already
released (using the BRAKE UNLOCK
button) no output is provided.
2. Test connectors CN1, CN2A and CN2B
from the back while attached to the relay box. All
connectors should be connected.
3. Activate each of the pendant control buttons
and measure the output voltage for the corresponding connector pins with a DC voltmeter. See figure
6-16. Meter should read 24 volts.
Figure 6-15. Relay Box Input
ACV
b. Test Results:
If you do not receive the correct meter readings,
the problem is in the input wiring, connectors or
components. If the correct readings are obtained,
proceed to the next step.
1
CN1, CN2A OR CN2B
16
CN2A
CN1
c. Checking Output to Pump
1. Disconnect pump connector CN15, connect
all other connectors and activate the AC120V
operating mode.
2. Test CN15 at pin 1(+) and pin 2(-) with a DC
voltmeter. Meter should read approximately 24-28
volts when any function button is activated. If no
voltage is present, use an ohmmeter to test the
continuity from CN15 to CN4 (yellow and blue
wires). Refer to figure 6-15 for CN4 pin locations.
FUNCTION
PINS
FUNCTION
PINS
Table Up
Table Down
Trend
Rev Trend
Tilt Right
Tilt Left
Reflex
Flex
1-2
3-4
5-6
7-8
9 - 10
11 - 12
13 - 14
15 - 16
Back Up
Back Down
Slide Foot
Slide Head
Kidney Up
Kidney Down
Leg Up
Leg Down
1-2
3-4
5-6
7-8
9 - 10
11 - 12
13 - 14
15 - 16
CN2B
Brake Set
Brake Unlock
1-2
3-4
Figure 6-16. Solenoid Output Connectors
Page 49
3500B
NOTE
The 15 amp battery protection fuse is in
the line between CN4 pin 1 and the
battery connector. Test the continuity
of the fuse if correct meter reading is not
received.
e. Test Results:
If you do not receive the correct meter readings, the
relay box is defective and should be replaced.
NOTE
•Before deciding the relay box is defective, check the wires and pins in the
connector blocks to make sure they
are not loose or making a bad connection with their mate.
•If the battery power is ON and no table
functions have been activated for 3
hours, the power off circuit will interrupt
the battery power.
b. CN4 to Pump Test
1. Disconnect connectors CN4, CN15 and
CN16. Leave all other connectors connected.
2. Using an ohmmeter, test for continuity
between the pins of CN4 and pins on CN15 and
CN16. See figure 6-18.
f. Checking Output to Pendant Control
The output to the Pendant Control can not be tested
without specialized equipment. If all tests have
been conducted and it appears that the Relay Box
is faulty, contact SKYTRON.
7
6
5
NOTE
The Relay Box connectors CN7 (Pendant Control), and CN8 (Auxiliary Base
Connector), are interchangeable.
CN-4
3
4
7
4
1. Disconnect connectors CN4 and the (+) and
(-) connectors from the batteries. Leave all other
connectors connected.
2. Using an ohmmeter, test for continuity
between pins 4, 5 and 6 of CN4, pins 1 and 2 of
CN14, and pin 4 of CN51. See figure 6-19.
CN51
(+)
53
CN4
6
6
5
CN4
4
3
2
1
CN14
2
(-)
CN-14
CN-4
CN-51
OHMS
1
5
6
4
4
0
0
0
2
Figure 6-17.
4
1
OHM
OHM
Page 50
1
2
OHMS
0
0
0
0
c. CN4 to Charging Box Test
7
4
3
2
1
CN-16
Figure 6-18.
2. Using an ohmmeter, test for continuity
between pin 1 of CN4 and battery (+) connector.
Also test between pin 2 of CN4 and battery (-)
connector. See figure 6-17.
6
5
CN-15
1
2
1. Disconnect connectors CN4, CN14 and
CN51. Leave all other connectors connected.
a. CN4 to Batteries Test
7
CN15 OR CN16
CN4
OHM
6-10. Main Wire Harness Continuity Tests
If correct meter readings are not received in tests
between components, before replacing the components, test the Main Wire Harness to be sure all
connectors and wires are making a good connection.
2
1
4
3
2
1
Figure 6-19. CN4, CN14, and CN51
3500B
3. Use a DC voltmeter and measure the
voltage across the 2 pin connector. Pin 1(+), and
pin 2(-). Meter should read approximately 24-28
volts.
NOTE
•The appropriate pendant control button must be pushed during this test.
The motor will run when this test is
performed, and the brake locking solenoid will be activated by any function
other than MOVE.
6-11. Solenoids
The solenoids are energized by 24 volt potential
that is controlled by the relay box.
The solenoid windings are protected from excessive heat by an internal thermal fuse that will open
after approx. 7 minutes of continuous operation.
The solenoid must be replaced if the internal thermal fuse has been blown.
The solenoids are mounted directly on either side
of the hydraulic mini-valves and push the spool
valve in one direction or the other depending upon
which solenoid is activated.
•If a solenoid does not function when
the pendant control button is pushed,
the problem could be the pendant control, the relay box, or the solenoid.
a. Solenoid Test
The following tests will check the voltage applied
to the solenoids and the resistance of the solenoid
coil.
c. Test Results:
If you do not receive the correct voltage, the problem could be in the wires leading down to the
connector. The problem could also be in the relay
box or the Pendant Control (refer to appropriate
section for troubleshooting).
b. Test #1
1. Activate either BATTERY or AC120V operating mode.
2. Disconnect the 2 pin connector from the
solenoid in question, all other connectors should be
connected. See figure 6-20.
OHM
If the correct voltage is obtained, everything is good
up to that point and the problem is more than likely
the solenoid.
ACV
BLUE
BLUE
WHITE/BLUE
RED
BLUE
BLUE
WHITE/BLUE
BLUE
BROWN
BLUE
WHITE/BLUE
BLUE
ORANGE
BLUE
WHITE/BLUE
BLUE
BROWN/WHITE
BLUE
WHITE/BLUE
BLUE
WHITE/BROWN
BLUE
WHITE/BLUE
BLUE
WHITE/GREY
BLUE
WHITE/BLUE
BLUE
PURPLE
BLUE
CN1
WHITE/
BLUE
UP
HD
DN.
RT.
REFX
UP
DN.
WHITE
BLUE
WHITE/
BLUE
UN
LOCK
UP
FT.
KIDNEY
TABLE
SLIDING
DN.
HD.
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
BLUE
BLACK/
WHITE
CN2B
ELEV.
DN.
TREND
HD
UP.
LAT.
TILT
LT.
FLEX
FLEX
BACK
SECT.
DN.
LEG
SECT.
UP
4
3
2
1
BRAKE
LOCK
BLUE
BLUE
BLUE
WHITE/BLUE
WHITE/BLUE
BLUE
BLACK
BLUE
WHITE/BLUE
BLUE
WHITE/PURPLE
BLUE
WHITE/BLUE
BLUE
GREY
BLUE
WHITE/BLUE
BLUE
BLUE/WHITE
BLUE
WHITE/BLUE
BLUE
RED/WHITE
BLUE
WHITE/BLUE
BLUE
WHITE/ORANGE
BLUE
WHITE/BLUE
BLUE
YELLOW
BLUE
WHITE/BLUE
WHITE/RED
BLUE
WHITE/BLACK
CN2A
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
Figure 6-20. Solenoid Test
Page 51
3500B
d. Test #2
The solenoid can be checked out using an ohmmeter R x 1 scale.
1. Measure the resistance between the two
pin connector in question as shown in figure 6-20.
Connector must be disconnected. Polarity of
meter leads is not important.
2. The meter should read approximately 16
ohms at room temperature.
3. Measure the resistance between either pin
and ground.
4. Meter should read infinity.
e. Test Results:
If the solenoid does not check out with the meter,
it is more than likely defective and must be
replaced.
NOTE
Whenever there are several components of the same type, a defective
unit can also be detected by substituting a known good unit or wire connector. In some cases this may be
faster than using a multi-meter.
6-12. Motor/Pump Assembly
The hydraulic pump motor is a 24 volt DC electric
motor. The oil pump unit is attached to the bottom
of the motor and is a gear type displacement
pump with a pumping capacity of .4 liter per min.
The Motor/Pump Assembly is mounted on insulators in the base of the table.
a. Motor/Pump Test
1. Disconnect motor connector CN15. Leave
all other connectors connected and activate either
BATTERY or AC120V operating mode.
2. Activate any function and use a DC voltmeter to measure across the two pin connector. Pin
1(+) and pin 2(-). See figure 6-21. Meter should
read 24-28 volts.
Page 52
CN15
DCV
2
1
Figure 6-21. Motor Input Voltage
NOTE
If the pump has been activated continuously for 1-1/2 to 2 minutes, the thermal
protector will interrupt the power to the
pump.
b. Thermal Protector Test
The Thermal Protector is built in to the pump motor
and is used to interrupt the current flow to the pump
motor to protect it from possible damage due to
overheating.
1. Turn OFF both BATTERY and AC120V
operating modes.
2. Use an ohmmeter to test for continuity
between terminals 1 and 2 on the connector CN16.
See figure 6-22.
CN16
DCV
2
1
Figure 6-22. Thermal Protector
3. The Thermal Relay should reset itself after
approximately one minute.
4. The Thermal Relay should activate after 11/2 to 2 minutes of continuous pump operation.
c. Motor Resistance Test
The motor can be statically checked for resistance
using an ohmmeter. This test is not 100% accurate
because you are checking the motor with very low
voltage from the meter and without any load.
1. Using an ohmmeter R x 1 scale, measure the
resistance between the two pins of CN15. See
figure 6-22.
3500B
2. The meter should read 1 to 2 ohms at room
temperature.
3. Measure the resistance between either pin
and ground.
4. Meter should read infinity.
d. Test Results:
If you do not receive the correct meter readings, the
motor or wiring is defective.
The slide function has inhibit switches to prevent
damage to the back and leg sections. If the back
section is below horizontal the top will not slide
toward the foot end. If the leg section is lowered
more than 45° below horizontal the top will not slide
toward the head end. Likewise, if the top is slid
toward the foot end, the back section will not go
below horizontal. If the top is slid toward the head
end, the leg section will not go more than 45° below
horizontal.
6-13. Return-to-Level Micro-Switches.
The return-to-level system for the Model 3500B is
the same as non-battery models except for the
wiring and connection to the relay box.
The return-to-level feature is activated by a single
button on the pendant control and automatically
levels the major table functions, lateral tilt, trendelenburg, flex, back section, and leg section.
The kidney lift has a back section-up inhibit switch
to prevent the table back section from damaging
the kidney lift when the lift is raised. The back
section still has the capability to be lowered and
raised, but will not raise more than 45° above
horizontal until the kidney lift is completely down. If
the back section is raised more than 45° above
horizontal, the system will not allow the kidney lift to
be raised.
NS-6
CS-3
NS-7
CS-2
The return-to-level/inhibit system consists of 12
micro-switches, an electrical connector, 2 terminal
strips and the related wiring. The micro-switches
are mounted on or adjacent to the function they
control and are wired for normally open or normally
closed operation. The micro-switches are cam or
lever actuated and can be adjusted at the individual
switch mounting brackets. See figure 6-23.
The micro-switches operate on low voltage, and
control the function circuits (pump/motor and appropriate solenoid valves) when activated by the
pendant control RETURN button.
The micro-switches are wired to the relay box
through 2 terminal strips, a riser cord and the 15 pin
connector CN10. See figure 6-23 for switch location and identification.
CS-1
CS-5
NS-1
NS-4
NS-3
TS-1
TS-2
NS-2
NS-5
CS-4
RELAY BOX
CN10
NS-1
NS-2
NS-3
NS-4
NS-5
NS-6
NS-7
TREND
REV. TREND
TILT LEFT
TILT RIGHT
BACK - DOWN TO LEVEL /SLIDE INHIBIT
BACK - UP TO LEVEL
LEG - DOWN TO LEVEL
CS-1
CS-2
CS-3
CS-4
CS-5
SLIDE/LEG DOWN INHIBIT
SLIDE/BACK DOWN INHIBIT
KIDNEY/BACK 45˚ UP INHIBIT
LEG DOWN 45˚/SLIDE INHIBIT
BACK UP 45˚/KIDNEY UP INHIBIT
Figure 6-23.
Page 53
3500B
6-14. Return/Inhibit System Troubleshooting
a. Switch Test
If a problem is suspected in the return circuits,
disconnect the connector CN10 from the Relay
Box to eliminate the circuits. Ensure that all table
functions operate properly using the Pendant Control. If the functions do not work properly using the
Pendant Control, refer to the appropriate test section and make all needed repairs before working on
the return circuits.
Turn Main Power ON, lock the table brakes, and
place the table top sections in a level position with
the Kidney Lift down. Disconnect connector CN10
from the relay box and using an ohmmeter, test the
wiring and switch operation at the appropriate pin
numbers for the micro-switch in question as shown
in figures 6-25 through 6-32.
NOTE
NOTE
It is normal for the back section to move
up if the RETURN button is pushed
when connector CN10 is disconnected
from the relay box.
Be sure to isolate the circuit when making continuity checks.
NOTE
If you do not receive the proper continuity results at connector CN10 it does
not necessarily mean the micro-switch
is defective. There could be a problem
with the riser cord between connector
CN10 and terminal strips 1 and 2, or in
the wiring from the switch to the terminal
strips. Further tests will have to be
made to determine the exact problem.
All of the micro-switches are connected to the relay
box via a wiring harness and the micro-switch riser
cord from terminal strips 1 and 2 to connector
CN10. The terminal strips are located under the
hose cover on the top of the elevation column.
Connector CN10 plugs into the relay box and is the
most convenient location to make circuit continuity
checks. See fig. 6-24 for connector pin locations.
TS2
8
7
CS-5
KIDNEY LIFT - INHIBIT
BACK UP 45˚ - INHIBIT
BACK DOWN - INHIBIT
LEG DOWN - INHIBIT
SLIDE HEAD - INHIBIT
LEG DOWN - RETURN TO LEVEL
CS-5
CS-3
CS-2
CS-1
CS-4
NS-7
CS-3
CS-2
CS-1
6
5
4
3
CS-4
2
NS-7
1
8
BACK UP - RETURN TO LEVEL
BACK DOWN - RETURN TO LEVEL
SLIDE FOOT - INHIBIT
TILT RIGHT - RETURN TO LEVEL
TILT LEFT - RETURN TO LEVEL
REV. TREND. - RETURN TO LEVEL
TREND. - RETURN TO LEVEL
NS-6
NS-5
NS-5
NS-4
NS-3
NS-2
NS-1
NS-6
7
NS-5
6
5
NS-3
NS-4
4
3
NS-2
NS-1
2
1
GREY
PURPLE
ORANGE/WHITE
ORANGE
14
13
BLACK/WHITE
12
BLACK
11
BROWN/WHITE
10
BROWN
9
PINK
RED/WHITE
8
7
RED
6
LIGHT BLUE
5
GREEN
4
YELLOW
3
BLUE
2
WHITE
TS1
Figure 6-24. Return / Inhibit Micro-Switch Test
Page 54
15
1
CN10
3500B
1
WHITE
NC
5
LIGHT BLUE
NO
NS-1
1
COM
15
2
COM
CN-10
NO
2
BLUE
NS-1. Trendelenburg
Test at pins 1 & 15
NS-2
NC
TS-1
NS-2. Reverse Trendelenburg
Test at pins 2 & 15
Table
Position
Switch
Position
Meter
Reading
Table
Position
Switch
Position
Meter
Reading
Level
Head Up
Head Dn
Open
Open
Closed
Infinity
Infinity
0
Level
Head Up
Head Dn
Open
Closed
Open
Infinity
0
Infinity
When table is in Trendelenburg Position,
NS-1 brings the top back to level.
When table is in Reverse Trendelenburg
Position, NS-2 brings the top back to
level.
Figure 6-25. Trendelenburg Return Switches
NS-3
NS-4
4
15
3
CN-10
NS-3. Lateral Tilt-Left
Test at pins 3 & 15
4
GREEN
5
LIGHT BLUE
3
YELLOW
NO
COM
COM
NO
TS-1
NS-4. Lateral Tilt-Right
Test at pins 4 & 15
Table
Position
Switch
Position
Meter
Reading
Table
Position
Switch
Position
Meter
Reading
Level
Tilt Right
Tilt Left
Open
Open
Closed
Infinity
Infinity
0
Level
Tilt Right
Tilt Left
Open
Closed
Open
Infinity
0
Infinity
When table is inTilt-Left Position, NS-3
brings the top back to level.
When table is in Tilt-Right Position, NS-4
brings the top back to level.
Figure 6-26. Lateral Tilt Return Switches
Page 55
3500B
NS-6
6
7
15
8
TS-1
15
8
NO
RED/WHITE
COM
PINK
PINK
RED
5
6
TS-1
CN-10
NO
COM
NS-5
NOTE
When CN-10 is disconnected, BACKDOWN function will not operate.
NS-5. Back Section Down
Test at pins 5 & 15
NS-6. Back Section Up
Test at pins 6 & 15
Table
Position
Switch
Position
Meter
Reading
Table
Position
Switch
Position
Meter
Reading
Level
Back Dn
Back Up
Closed
Open
Closed
0
Infinity
0
Level
Back Dn
Back Up
Open
Open
Closed
Infinity
Infinity
0
When the Back Section is Down, NS-5
brings the Back Section Up to level and
will not allow Top Slide toward foot.
When the Back Section is Up, NS-6
brings the Back Section Down to level.
Figure 6-27. Back Section Return Switches
NS-7
1
BROWN
7
15
CN-10
8
GREY
NC
NO
TS-2
NS-7. Leg Section Down
Test at pins 7 & 15
Table
Position
Switch
Position
Meter
Reading
Level
Leg Dn
Open
Closed
Infinity
0
When the Leg Section is Down, NS-7
brings the Leg Section Up to level.
Figure 6-28. Leg Section Return Switches
Page 56
COM
3500B
NOTES
SLIDE function will not operate when
CN-10 is disconnected.
3
9
4
10
15
7
CN-10
TS-2
BLACK
BLACK/WHITE
PURPLE
NC
COM
CS-2
CS-1. Leg Down 45˚ Inhibit
Test at pins 9 & 15
NC
COM
CS-1
CS-2. Back Down Inhibit
Test at pins 10 & 15
Table
Position
Switch
Position
Meter
Reading
Table
Position
Switch
Position
Meter
Reading
Center
Slide Hd
Slide Ft
Closed
Closed
Open
0
0
Infinity
Center
Slide Hd
Slide Ft
Open
Closed
Open
Infinity
0
Infinity
When Top is slid toward head, CS-1 will
not allow Leg Section to go more than
45˚ below horizontal.
When Top is slid toward foot, CS-2 will
not allow Back Section to go below
horizontal.
Figure 6-29. Leg Down / Back Down Inhibit Switches
CS-3
COM
NC
GREY
8
ORANGE
5
TS-2
15
11
CN-10
CS-3. Back Up Inhibit Switch
Test at pins 11 & 15
Table
Position
Switch
Position
Meter
Reading
K-Lift Dn
K-Lift Up
Open
Closed
Infinity
0
When K-Lift is Up, CS-3 will not allow
Back Section to go more than 45˚ above
horizontal.
Figure 6-30. Back Up Inhibit Switches
Page 57
3500B
CS-4
2
BROWN/WHITE
8
8
15
CN-10
GREY
NC
NO
TS-2
CS-4. Slide Inhibit
Test at pins 8 & 15
Table
Position
Switch
Position
Meter
Reading
Level
Leg Dn
Open
Closed
Infinity
0
more than 45˚
When Leg Section is more than 45˚
below horizontal, CS-4 will not allow Top
to Slide toward head.
Figure 6-31. Slide to Head Inhibit Switches
CS-5
NO
6
ORANGE/WHITE
COM
PURPLE
7
TS-2
12
15
CN-10
CS-5. Slide Inhibit
Test at pins 12 & 15
Table
Position
Switch
Position
Meter
Reading
Back Up Less Than 45˚
Back Up More Than 45˚
Open
Closed
Infinity
0
When Back Section is more than 45˚ above horizontal, CS-5 will not allow Kidney Lift to operate.
Figure 6-32. Kidney Lift Inhibit Switches
Page 58
COM
3500B
b. Switch Adjustment.
If proper readings are not obtained during test or if
table does not properly return to level, use the
following procedure to adjust the switches.
1. Apply table brakes and (using a level) level
the table top using the TRENDELENBURG and
LATERAL-TILT function buttons on the pendant
control.
2. For all switches except the Leg Section
switches, carefully loosen the switch retaining
screws, and adjust the switches as needed. See
figure 6-33.
RETAINING
SCREWS
3. To adjust the Leg Section switches loosen
the jam nuts, adjust the switch, and tighten the jam
nuts. See figure 6-34.
PHILLIPS HEAD
SCREWS
LEG SECTION
MICRO-SWITCH
BRACKETS
Figure 6-34. Leg Section Micro-Switch
Adjustment.
MICRO-SWITCH
Figure 6-33. Micro-Switch Adjustment
Page 59
SECTION VIII ELECTRICAL SYSTEM ADJUSTMENTS
7-1. Relay Box Adjustments
The Relay Box contains variable resistors for adjusting the operating timers for the BRAKE SET
and BRAKE UNLOCK functions. The Relay Box
for the battery model tables also has variable
resistors for setting the Power Off timer and the
battery recharge warning circuit. These timers are
set at the factory and usually never need adjustment. If an adjustment is necessary, remove the
relay box cover and use the following procedures.
See figures 7-1 through 7-3.
VR-1
a. Brake Release Timer
The Brake Release Timer is set for about 7 seconds and is controlled by the variable resistor VR1
on the relay box circuit board. Turn the adjuster
clockwise to increase the operating time. Counterclockwise to decrease the operating time.
b. Brake Set Timer
The Brake Set Timer is set for about 7 seconds and
is controlled by the variable resistor VR2 on the
relay box circuit board. Turn the adjuster clockwise to increase the operating time. Counterclockwise to decrease the operating time.
VR-2
Figure 7-1. Relay Box Adjustments Model 3500
Page 60
VR-3
VR-1
VR-2
CN-3
CN-4
VR-4
CN-2B
CN-2A
CN-1
Figure 7-2. Relay Box Adjustments Model 3500B
Page 61
RELAY BOX
HOSPITAL GRADE PLUG
+5V
CN8
2
GND
1
3
MNPC-32
MNPC-33B
1
CN3
2
3
3
4
4
5
#RL-42
7
9
#RL-41
10
11
9
10
11
13
#RL-29
18
19
15
DSW2
20
16
21
22
17
23
18
24
25
26
19
17
22
CN4
RL-1
RL-2
#RL-2
28
#RL-3
D6
#RL-30
10
1
2
9
1
#RL-6
10
2
12
#RL-43
#RL-27
11
1
12
2
13
1
14
2
15
1
16
2
1
1
2
2
3
1
4
2
5
1
6
2
14
1
#RL-35
2
15
#RL-41
#RL-42
#RL-34
16
17
#RL-31
19
RL-7
RL-8
#RL-8
RL-9
#RL-9
RL-10
#RL-10
#RL-26
RL-11
#RL-11
RL-12
#RL-12
7
1
RL-13
#RL-13
8
2
9
1
RL-14
#RL-14
10
2
R12
11
1
RL-15
#RL-15
12
2
13
1
RL-16
#RL-16
14
2
15
1
RL-17
#RL-17
16
2
17
1
18
2
19
1
20
2
#RL-45
TM2
R11
DSW1 1
2
3
4
10
33 32 31 30 29 28 27 D26
16
D34
RL-43
#RL-25
D35
2
RED
7
6
CS-4
BROWN-WHITE
COM
CS-1
NC
7
RL-31
RL-32
2
8
RL-33
RL-34
9
RL-35
RL-36
BLACK
NO
BLACK-WHITE
4
CS-2
ORANGE
CS-3
ORANGE-WHITE
5
7
8
6
SV-14
SV-15
SV-16
SV-17
RL-18
SV-18
CN-38
#RL-19
RL-19
21
RL-25
RL-26
RL-27
RL-28
RL-29
RL-30
1
3
#RL-18
D18
#RL-27
D38
#RL-35
D39
10
RL-37
RL-45
11
RL-38
12
RL-39
RL-40
D19
#RL-20
RL-20
22
23
D20
#RL-39
BROWN
NS-7
SV-13
CN-37
D17
4
NS-6
8
20
D37
5
RED-WHITE
19
D36
5
SV-12
CN-36
D16
RL-44
3
SV-11
CN-35
D15
17
SV-10
CN-32
14
15
SV-9
CN-34
12
ON
#RL-36
6
D13
18
NS-2
NS-5
SV-8
CN-31
11
#RL-34
1
NS-4
SV-7
CN-33
9
CN2
GREEN
D12
#RL-24
13
26
4
R8
4
#RL-37
#RL-36
25
YELLOW
SV-6
CN-29
8
#RL-32
22
D10
D11
7
#RL-44
20
21
3
6
#RL-37
24
3
SV-5
CN-26
#RL-7
5
18
23
NS-3
SV-4
CN-30
CN5
#RL-29
13
2
SV-3
CN-25
D9
#RL-38
11
BLUE
2
8
#RL-39
8
WHITE
1
6
SV-2
CN-28
D8
9
1
5
SV-1
CN-27
D7
7
NS-1
2
7
30
6
TM1
1
4
#RL-5
5
CS-1B ACK DOWN- PR OHIBIT
CS-2LEG DO WN- PR OHIBIT
CS-3PR OHIBIT BACK UP
CS-4LIMIT OF SLIDING TOWARD HEAD
CS-5LIMIT OF KIDNEY BRIDGE UP
3
RL-5
RL-6
29
4
LEVEL
LEVEL
LEVEL
LEVEL
LEVEL
LEVEL
LEVEL
2
RL-4
2
NS-1HEAD DO WNNS-2HEAD UP NS-3RIGHT UP NS-4LEFT UP NS-5B ACK DOWNNS-6B ACK UPNS-7LEG DO WN-
1
2
#RL-4
D5
3
24
1
CN-24
D4
26
30
75µF
CN-21
27
29
180V
CN5
CN-23
D3
25
27
M
R6
24
26
C
2
T2
#RL-1
RL-3
22
23
25
200W
60Hz
3
CN-22
1
23
C7
D2
20
24
R10
TRA1
21
23
CN9
3
G
P.M
CN15
1
S
R5
TR4
60Hz
AC115V
#RL-21
18
28
21
D1
19
22
AC115V
F2, FH2
TR3
5
16
20
10A
2
PB10SU
D21
17
21
20
GND
D24
SW1
AC
4
RL-21
14
18
#RL-40
ON
R4
PS
15
19
1
2
3
4
5
6
7
8
9
10
+
C4
D14
12
16
17
14
TR2
VR2
1
+5V
#RL-23
13
15
R3
D25
+ C1
T1
10
14
16
VR1
11
12
15
13
TR1
R2
8
10
14
12
6
9
11
13
C3
+
7
8
12
RL-24
D24
4
6
9
RL-23
R1
5
7
#RL-42
8
7
8
3
5
#RL-41
6
6
#RL-22
2
4
5
R7
1
2
C2
#RL-22
CN1
1
R9
F1, FH1
D40
#RL-30
24
D22
RL-22
D23
C5
+
RL-22
D41
#RL-38
C6
+
#RL-25
BRAKE
(SET COIL)
TIMER
BRAKE
(RESET COIL)
TIMER
#RL-28
#RL-31
CS-5
13
#RL-33
14
15
Wiring Diagram, Model 3500
Page 63
MNPC-68
R16
IC7
1
C10
IC2
5V
+
12
11
10
9
8
7
6
5
27
28
23
25
4
28
29
3
2
C12
C9
16 15 14 13 12 11 10 9
R11
R14
R15
R12
CN7
#RL-25
NF1
R7
1
2
R8
D5
TR6
GND
1 2
TR5
R9
C8
R10
VDD OSC C2 C3 SP1 2
R X IN
IC1
3
4
TC9149
HP1 2 3 4 5 6
3 4 5 6 7 8
R13
+5v
3
4 GND
5
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
A16
PGM
Vpp
Vcc
D0
D1
D2
D3
D4
D5
D6
D7
NC
CE
OE
1
24
9
10
8
7
6
5
4
18
17
20
19
14
13
16
15
11
1
Q0
C13
Q1
Q2
Q3
2
3
21
22
2354
RN1 1
23
12
30
22
9
5V
2
2
3
3
4
4
5
5
6
6
7
7
IC8
1
18
8
6
HN27C101AG-10
1
#RL-2
RL-3
7
D14
8
1
9
D15
10
1
11
D16
12
1
13
D17
14
1
15
D18
16
1
RL-4
#RL-5
RL-5
#RL-6
RL-6
#RL-7
RL-7
#RL-8
8
#RL-37
14
4 GND
10
10
11
11
C17
D6
#RL-37
5V
IC5
12
12
13
13
1
24
9
10
8
7
6
5
4
18
17
20
19
14
13
16
15
11
7
Q0
Q1
CN9
1 Q0
(HP1)
Q2
2 Q1
(HP2)
Q3
3 Q2
(HP3)
4 Q3
(HP4)
SP5
7
+5v
ZNR35
22
7
TREND.
SV-4
CN24
2
SV-5
CN25
2
TILT
SV-6
CN26
2
SV-7
CN27
2
FLEX
SV-8
CN28
2
1
3
D20
4
1
5
D21
6
1
7
D22
8
1
9
D23
10
1
14
14
11
D24
12
1
15
15
13
D25
14
1
15
D26
16
1
#RL-20
17
D27
18
1
#RL-21
19
D28
20
1
#RL-11
RL-11
#RL-12
#RL-13
RL-13
IC6
IC9
1
18
16
16
17
17
#RL-14
RL-14
#RL-15
RL-15
#RL-16
RL-16
RL-35
#RL-26
RL-17
9
TC4514BP
ZNR36
5V
C20
GND
8
21
23
12
HP5
6
3
2354
RN2 1
5
2
SV-3
CN23
2
1
D19
2
RL-10
RL-12
C16
6
ELEV.
SV-2
CN22
CN2A
#RL-10
RL-9
5V
1
5V
CN21
2
#RL-4
C19
5
1
1
9
5V
2
7
SV-1
3
D12
4
5
D13
6
#RL-9
9
9
RL-25
2
RL-8
CN8
1 NF2
3 +5v
1
D11
2
#RL-3
C23
14
1
RL-2
8
5V
IC11
7
CN1
#RL-1
1
C18
TC4514BP
24
16
MNPC-70
RL-1
C15
31
32
13
14
15
17
18
19
20
21
1
18
CN5
5V
IC4
5V
5V
C11
CN6
18
18
19
19
20
20
BACK
SV-10
CN30
2
SV-11
CN31
2
SLIDE
SV-12
CN32
2
SV-13
CN33
2
K-BRIDGE
SV-14
CN34
2
SV-15
CN35
2
LEG
SV-16
CN36
2
SV-17
CN37
2
BRAKE
SV-18
CN38
2
CN2B
RL-18
ZNR31 ZNR32 ZNR33 ZNR34
SV-9
CN29
2
RN3
IC3
5
ZNR19
4
4
ZNR20
NS-4
NS- 5
5
6
ZNR21
6
7
8
NS-6
ZNR22
NS- 7
7
1
ZNR23
CS-4
8
2
ZNR24
COM
CS-1
NC
9
3
ZNR25
NO
10
4
NC
1
C14
13
14
15
17
18
19
20
21
21
9
5V
C41
22
23
23
LOCK
+
RL-22 RESET
C4
+
C5
24
RL-26
25
25
26
26
R3
#RL-22
RL-21
UNLOCK
24
+ C6
#RL-18
RL-19
D7
D3
RL-27
1 2 3 4 5
22
24
OE
16
CE
#RL-17
RL-20
VS1
30
22
R-28
6
RL-23
TR1
#RL-38
#RL-35
R5
#RL-24
27
#RL-36
27
RL-37
ZNR28
13
28
RL-38
5V
28
29
5V
30
30
GND
VS2
D29
2
3
+
C36
#RL-30
+
R17
R18
D8
R19
1
4
2
D9
R21
TR7
R20
#RL-28
+
#RL-31
C37
VR3
R22 R24
C39
+
TR9
+
C38
TR8
D30
5
RN4
RN5
1
+24V
1
ACK DOWN-
OHIBIT BACK UP
6P
CN51
MNPC-41A
10A UL
FH032
6
SW7
2SD1525
3
FH1, F1
CN13
1
SC1
1
100V
+
+
2
2
200VA
2
2SD468
TR51
R56
56 W
BR252
6
2.2 KW
R55
R23
R52
1.5 KW
D52
3 W 3W
2
R58
R54
CN14
D51
SC2
1
3 KW
LINE
5
POWER
24DC 3
C50
4
2
7
VR51
RL-40
BR252
12V
R51
1.2 KW
2
6
7
4
BAT2
UL
3
1
4
2
CN15
#RL-33
PUMP
MOTOR
PM1
6
1
2
CN16
1
+
D53
BAT1
RL-33
2SC1815
TR53
1000 P
C52
15A
NPH16 - 12
DC12V
F-66AD
FH3
F3
THERMAL
PROTECTOR
R25
VR4
TR11
R26
TR10
2
7
8
2P
150 W
5A
ICN1
3P
RL-29
#RL-40
2SD468
TR52
CN4
1
5
3
C51
SB-25
3P
5
B
R57
150 W
3W
22V
FH2, F2
1
4
E
TR54
470µF
50V
TR1
CN12
1
RL-28
5
C
10A
GND
#RL-27
LP1
WN-
UL. CSA AC
CORD 1
Page 64
+24V
4
8P
Wiring Diagram, Model 3500B
#RL-32
R17
CN11
CS-1B
PROHIBIT
CS-2LEG DO
PROHIBIT
CS-3PR
+
#RL-29
SR1
3
CN3
#RL-27
RL-30SET
#RL-30
1
NS-1HEAD
DOWNLEVEL
NS-2HEAD UP
- LEVEL
NS-3RIGHT UP
- LEVEL
SW6
R27
C22
TM2
15
16
1 2 3 4 5
29
SW5
14
UNLOCK
RL-34
15
5V
TM1
ZNR30
13
VR2
R6
RL-30RESET
5V
12
D2
TR4
C7 +
SW4
11
TR3
ZNR29
14
9
10
LOCK
+5V
#RL-39
SW3
8
TR2
RL-24
HN27C101AG-10
7
D1
VR1
R4
#RL-23
SW2
5
+5V
D4
ZNR27
CS-5
4
RL-22 SET
C21
12
6
21
RL-39
11
5
CS-3
8
D0
D1
D2
D3
D4
D5
D6
D7
3
ZNR26
CS-2
7
Vcc
SW1
2
RL-32
ZNR18
3
3
Vpp
1
18
31
32
RL-31
2
2
PGM
#RL-34
NS-2
A0
A1
A2
A3
A4
A5
A6
A7
A8
A9
A10
A11
A12
A13
A14
A15
A16
#RL-24
12
11
10
9
8
7
6
5
27
28
23
25
4
28
29
3
2
ZNR17
NS- 3
1
5V
CN10
#RL-36
SET
1
1
RL-36
RESET
NS-1
IC10
#RL-23
#RL-19
1
D31
+
C40
D10