Hardware setup
Connect power
Digi WR54 Hardware Reference
21
For DC installations (with a fixed system ground reference), ground the WR54 chassis to the system
ground reference.
For proper grounding reference:
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Attach the device to a grounded metal surface.
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Connect one end of a short AWG or larger gauge wire to the upper-right grounding hole and
connect the other end to the vehicle chassis.
Special considerations
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Separate Ethernet and power cables from other wiring in the vehicle and route the cables
away from sharp edges.
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Use cable strain relief for installations in high-vibration environments.
WR54 electrical rating
WR54 devices require connection to a conditioned power system that meets these requirements:
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Tolerance within maximum operating voltage range 9 VDC to 36 VDC.
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on the back of the device requires wiring terminals with the following
specifications:
Wire size: 30-12 AWG
Wire type: copper wire only
Terminal blocks torque: 5-7 pounds per inch
For supply connections, use wires suitable for at least 85° C.
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Power installation must be performed by a qualified electrician, following the National
Electrical Code, ANSI/NFPA 70 and Canadian Electrical Code, Part I, CSA C22.1.
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There must be a disconnect device in front of WR54 devices to protect maintenance workers.
Use a 20 A circuit-breaker as the disconnect device.
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Before doing any maintenance, the maintenance worker must use caution and close the
general power supply.
WR54 power connector
The WR54 has a power connector located on the back of the device:
Pin
Connection
1
Ignition sensor
2
Positive
3
Negative
See
for information on connecting power to the device.
