Download 9550-9142_5 - Scott Safety

4800A NIC II LE LMa
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a nt sm
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7 Maintenance
WARNING!
B efore perform in g an y m ain ten an ce proced u res th at requ ire
th e tran sm itter h ou sin g, d etector h ead , or an y oth er electrical
en closu re to be open ed , be su re to d eclassify th e area to n on hazardous.
It is advisable that spare transmitter circuit boards and sensors be on hand to
facilitate maintenance. The following sections describe how to:
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•
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Perform routine maintenance
Replace the sensor
Replace a transmitter circuit board
Readjust the LCD’s electrical SPAN (R19) and ZERO (R20) readings
7.1 Routine Maintenance
Routine maintenance consists of simply calibrating the transmitter as described in
Section 5.6 Routine Calibration (Non-Intrusive) on a periodic basis.
Check calibration of the transmitter once a week for the first month of operation;
monthly, or as experience dictates thereafter.
7.2 Replacing the Combustibles Sensor
Remove power from the transmitter. Then disassemble the detector head and
replace the sensor as shown in either Figure 7-1, 7-2, or 7-3.
After replacing the sensor, perform the procedures in Sections 5.4.2 Sensor Voltage
Check, 5.4.4 Balance Adjustment, 5.5 Checking Sensor Output Signal Strength,
and 5.6 Routine Calibration.
Figure 7-1.
S en sor R eplacem en t,
6V "Gold Bell" Diffusion
Head Assembly
Note: See Appendix C for
5.5V Scott Stainless Steel
Detector, view Figure C-6
6V "GOLD BELL" CONFIGURATION
Page 52
Scot t H ea lt h & Sa fet y
In st r u ct ion 9550-9142 Rev. 5