Recommended Wire And Circuit Breaker For 12V Pin On Trailer 7-Way Connector
Question:
So I read on here that its ok to put a 40A breaker on a 12V circuit to a 7 pin trailer connector using 12AWG strand wire. That sounds like way too much amperage for a wire that size. Now, I teach AC electricity and DC digital electronics and according to my calculations and charts, 6AWG wire should be used for carrying 40 or less amps. I am actually running a 12V line back to my 7 pin on my truck using 10AWG strand wire and now Im wondering what size breaker is really ok? I think Im missing something here and would appreciate the help. This is a 30 year old classic pickup in amazing shape and Id hate to cause a fire. Thanks very much!
asked by: Jim V
Helpful Expert Reply:
For your 12V wiring to your 7-way, we have people running many different things off that 12V wire. 12 gauge or even better 10 gauge ensures that the power is transferred timely and accurately. We have a kit for brake controllers and 12V wiring for the 7-ways # 5506 that we've used for years. It uses 10 gauge wire and has a 20 amp, 30 amp and 40 amp circuit breaker. Normally the 30 amp # PK54230 or the 40 amp # 9510 is what we recommend with the 10 gauge wire # 10-1-1 for your application.
Products Referenced in This Question
40 Amp In-Line Circuit Breaker - Perpendicular Mount Bracket
- Accessories and Parts
- Wiring
- Circuit Breaker
- 40 Amp
- Pollak
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Circuit Breaker - 30 Amp - Perpendicular Mount Bracket - Cycling Auto Reset - Metal - Type I
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- Wiring
- Circuit Breaker
- 30 Amp
- Pollak
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Product Page this Question was Asked From
Wiring Kit for 2, 4, 6, and 8 Brake Electric Trailer Brake Controllers
- Accessories and Parts
- Trailer Brake Controller
- Installation Kits
- etrailer
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