What Would Cause Voltage Drop Between Front of Trailer and Brake Assemblies
Question:
I am working on trailer brakes on a 40ft gooseneck dual tandem axles l. I have 12 volts at the wires before the magnets tie in. When I plug in the wires to the magnets and it engages the brakes the volts will to 10 volts. Is this normal? Or should the stay at 12 volts? I am powering the brakes at the plug with a 12 volt battery. I have cleaned all grounds and connections. If the is not normal would I need to run bigger wire?
asked by: Derick K
Expert Reply:
Typically if there's a large voltage drop like you mentioned the issue is the longer run of wire not being a heavy enough gauge of wire. You'll need to use 10 gauge wire like 10-1-1 to make the run from the front of the trailer back to the assemblies and you'll see the voltage drop be much smaller.
Products Referenced in This Question
Product Page this Question was Asked From
Deka Jacketed 2 Wire, 10 Gauge, Brake Wire - per Foot
- Wiring
- Wire
- Jacketed Wire
- 2 Wire
- 10 Gauge
- Deka
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