Adding an External Battery to a 2018 Interstate Trailer with Trailer Breakaway Kit
Question:
I am adding an external battery for my interior lights as they do not work off the trailer brake battery when unplugged which wire do I use for my power in the trailer and before or after the trailer brake battery. I was told to watch out for a charge back problem? Thanks
asked by: Keith B
Helpful Expert Reply:
A trailer breakaway battery is a smaller battery that you definitely do not want to use to power the lights in your trailer with. As convenient as that would be, it could drain the battery enough that the breakaway battery would not activate your trailer brakes long enough to safely bring your trailer to a stop. Adding an external battery, as you are wanting to do, is the way that you want to go.
What you will want to do is use 10 Gauge Wire # 10-1-1 and run it to the pin in the 11 o'clock position (see attached picture) on your trailer side connector. This will enable you to receive a maintenance charge to your external battery while the vehicle is connected to the trailer. You will want to use the Roadmaster Single Park Light Diode # RM-690 to keep from that charge back problem happening.
Since this solution will only provide a charge that maintains the battery level you will want to use either the CTEK MULTI US 7002 # CTEK56353 to charge the battery while the trailer is parked, or the Redarc BCDC Battery Charger # 331-BCDC1240D and a Solar Panel # TLA7713 to trickle charge it from both the tow vehicle and solar panel while you are out on the road. I have attached a picture displaying the setup that includes the solar panel.
![Jon G](https://images.etrailer.com/static/images/catg/people/1086_tn.jpg)
Products Referenced in This Question
Redarc In-Vehicle BCDC Battery Charger - Dual Input - DC to DC - 12V/24V - 40 Amp
- Battery Charger
- Battery Charger
- RV/Camper
- Trailer
- 200 Ah
- Charges/Maintains
- 12V
- Solar Panels to Auxiliary Battery
- Vehicle Battery to Auxiliary Battery
- Redarc
more information >
Roadmaster Single Park Light Diode
- Accessories and Parts
- Flat Tow Wiring Harness
- Diodes
- Roadmaster
more information >
Solar Power Kit for TorkLift PowerArmor Battery Box - 10 Watt Panel
- Accessories and Parts
- Battery Boxes
- Battery Box Solar Kit
- TorkLift
more information >
Product Page this Question was Asked From
CTEK MULTI US 7002 12-Volt Universal Battery Charger w/ Pulse Maintenance and Backup Power
- Battery Charger
- Battery Charger
- Car/Truck/SUV
- Motorcycle
- Trailer
- Lawn Mower
- Jet Ski
- 150 Ah
- Charges/Maintains
- 12V
- Wall Outlet to Vehicle Battery
- CTEK Power Inc
more information >
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