What is Recommended Way to Charge Trailer Battery While Towing

Question:

I have a trailer battery that Id like to charge from the vehicle 7-way plug. It will be charging a battery for my trailers winch. If the 7-way is plugged in and charging the trailers winch battery while operating the winch pulling high amps, do I need a breaker in-place between the 7-way and the trailer battery? If so, what breaker do you recommend? Also, when the 7-way is charging the trailers winch battery, will it stop charging once it is fully charged? Thanks! Troy

asked by: Troy

Expert Reply:

You can put a maintenance charge on a trailer battery through the 12 volt circuit of the 7-way but you should note that it's not going to significantly charge a depleted battery. Commonly this circuit is protected with a 40 amp breaker like part # 9510 using 10 gauge wire like part # 10-1-1 (sold by the foot).

expert reply by: Jameson C