Siemens GCP5000 Instruction & Installation Manual page 221

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FAILURE TO FOLLOW THE RAILROAD'S OR AGENCY'S APPROVED
WIRING OR INSTALLATION GUIDELINES MAY LEAD TO POSSIBLE
UNSAFE OPERATION OF THE SYSTEM.
For a crossing without gates, disable the GP input to the A80405 module
by programming the Gates Used to NO.
4.5.4 Lamp Wire Length Limitations
The maximum single wire length between the Lighting Surge Panel and the Mast Junction Box
is determined by the:
•
Gauge of the wire
•
Total lamp current
•
Type of battery used
4.5.5 Maximum Lamp Wire Length
The maximum recommended lamp wire length for a crossing is listed in Table 4-3.
The designated load current is based on 9.5 volts supplied to lamps.
Generally, 18-watt bulbs draw 1.8 amps per bulb lit at the same time and 25-watt bulbs draw 2.5
amps per bulb lit at the same time.
If a lamp wire between the surge Panel and the Mast Junction Box is too
long, its resistance can prevent the full required voltage from being
applied to the lamps.
The effective resistance of a wire can be reduced and/or its maximum
length increased by using two wires of the same gauge in parallel as
indicated in Table 4-3.
The A80405 module maintains a constant lamp output voltage provided:


When the battery voltage supply cannot supply the requested lamp
voltage, a lamp voltage limited message will be displayed.
SIG-00-22-02
Version: B.1
The battery voltage to the SSCC remains 1.5 volts higher than the
lamp voltage measured at the SSCC L1 and L2 outputs.
The maximum lamp wire length is not exceeded.
4-17
SSCC APPLICATIONS & PROGRAMMING GUIDELINES
WARNING
NOTE
NOTE
JUNE 2022 (Revised September 2022)