Can Group 27 Battery Be Charged From 12V Circuit on 7-Way

Question:

can the 12v aux connection in a 7-way be used to charge a size 27 battery in my trailer? Tow vehicle is a 2019 f250 gas.

asked by: T. B

Expert Reply:

The 12V connection will not be sufficient to charge a size 27 battery. For example, a 12V battery on your trailer can be charged from your tow vehicle by simply running 10 gauge wire # 10-1-1 from the 12 volt circuit on the vehicle side connector to the positive post of your trailer battery. But even in this example, it will only provide a maintenance charge on a 12V when connected to the trailer, but not charge a depleted battery.

If you need to charge up a dead battery, you will need to use a charger like the CTEK Universal Battery Charger # CTEK56353 when 120V AC power is available. The CTEK charges batteries with capacities from 14 Ah - 150 Ah which would be sufficient for Size 27 batteries.

expert reply by: Patrick R