How to Charge a Trailer Battery Through a 7-Way Connector
Question:
I need to charge a marine 12v battery that powers a winch and tongue jack in a 24inch enclosed race car trailer. The tow vehicle is a Toyota Tundra and has 7 pin round connector. I want the trailer battery to charge from the Tundra when the 7 pin is connected.
asked by: Joseph F
Expert Reply:
You can put a maintenance charge on your trailer battery with the 12 volt accessory circuit of the 7-way. The 1:00 position of your 7-way carries this circuit. You would just need to run a length of 10 gauge wire like part # 10-1-1 (sold by the foot), from this pin to the positive terminal of the battery.
You should note that this won't charge a dead battery, but it will keep the battery topped off when you are towing the trailer.
Steve
7/30/2020
I don't understand why you don't think trailer battery will not be charged while in transit. Alternator will raise voltage to 14.2 V to run what ever electrical load vehicle and trailer are using. Alternator will produce what ever amp is required to maintain 14.2 amps. I am sure trailer battery will charge as long as wiring to trailer is sufficient to carry the load.
Mike
6/21/2020
@ChrisR Once I've connected the trailer battery for charging, will the battery charge when truck is running only, or continue to charge when the trailer plug is connected even though the vehicle is not running?
Products Referenced in This Question
Product Page this Question was Asked From
Starter Solenoid - SPST - 12 Volt - 100 Amp - Continuous Duty - Grounded
- Accessories and Parts
- Battery Boxes
- Switches and Solenoids
- 100 Amp
- Pollak
more information >
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Jim
8/11/2020
Would a diode be recommended in order to prevent the trailer battery from discharging the vehicle battery?