Download 100140-010 PMD-4 User Manual Draft (2)

Annual Warning Time Retest Procedures
The purpose of this procedure is to provide a method for reducing the time and effort needed to
perform the required FRA annual warning time tests. This is accomplished by identifying all
critical site specific switch and adjustment settings, which can affect warning time, and
assigning a single comprehensive CRC value hereafter called the Warning Time CRC (WT
CRC). The process of accomplishing this is to initially setup, test and document the operation
of the warning system. When testing has been satisfactorily completed, a Warning Time CRC
value is generated from the combined internal settings of the PMD-4 for the specific site. The
resulting unique Warning Time CRC number simplifies the verification of all of these settings.
This Warning Time CRC can be compared to later inspections to determine, conclusively, if
any site specific setting has been changed since the unit was last operationally verified and
documented. . If the two numbers agree, it is certain that no critical PMD-4 parameters have
been changed that would affect warning time. Provided that the Warning Time CRC and
additional display values specified below match their recorded values within specified limits,
the unit can be safely recertified.
The following verification form specifies the items that should be checked to verify the
warning time periodically after initial installation. Base testing values should be captured
upon initial installation or upon recertification of warning time operation. Mark any not
applicable items as NA. If the values differ from the specified ranges, then the original
process of initial setup, test, and documentation should be performed.
Periodic Warning Time Test Form For PMD-4/4R
Location
Equipment
Parameter
RX
Site Specific
Parameters
PMD-4/4R
Parameters to Verify
Type of Setting
RX is within 95
to 105 (91 to
109 if Auto RX
is disabled) and
is stable +/- one
digit.
Displayed
value
Verify the Warning
Time CRC value
from the CDU or
web GUI matches
base testing value
as recorded on the
Grade Crossing
Location Record
form.
Display Value
Base
testing
values
Current test Current test
- Standby
- Normal
Units
units
External Wiring
Activate the crossing
then verify the
crossing warning
devices all operate
as intended.
NA
NA
Remote Starts
Verify that the
remote start control
activates all crossing
warning devices as
intended.
NA
NA