Can 12 Volt Accessory Circuit on a 7-Way Trailer Connector be Used to Maintain a Deep Cycle Battery

Question:

I have a dump trailer that I use with a deep cycle battery. I saw in an earlier post that it is possible to use the 12v accessory circuit from my truck to maintain the batterys charge. Do I need a regulator of any kind to use the 12v accessory circuit, or can I clamp it directly to my battery and let it charge when my trailer is hooked up to my truck?

asked by: Travis C

Expert Reply:

The 12 volt accessory circuit on a 7-Way can maintain a battery, it just will not be able to charge it. Since we are talking about maintaining a charge, a regulator will not be needed since the 12 volt accessory circuit does not have the capacity to charge the battery. So it will not overcharge any of the cells.

Since a deep cycle battery is designed to discharge most of its charge at once, I would recommend connecting the 12 volt accessory circuit first to a 40 amp circuit breaker, # PK54540, and then to the battery to protect the deep cycle battery, the wiring, and the vehicle battery.

expert reply by: Michael H