Diode to Prevent Back Feeding from Trailer Battery to Running Lights
Question:
I have a small military type trailer that I built. I want to add a battery to it. I was hoping to run a charge wire off of the running lights. Which diode would be the best for something like this? I'm planning on running a couple of LED spot lights off of this battery and also have it as a backup jump start battery because I do overland exploring.
asked by: John K
Helpful Expert Reply:
For a diode I recommend # RM-790 which is rated for 85 amps. However, trailer wiring, both on the trailer and on the vehicle side, is too small to charge up a regular battery. And most vehicle alternators are unable to push back the amperage required to charge up a regular battery. At best it will provide a maintenance charge and keep the battery from depleting.
It can charge up a small breakaway batter such as # HM20008 though. But these batteries are rated much lower than a regular car battery, only 5 amp hours, and would be basically useless if you needed to jump start a vehicle.
In order to charge up a regular car battery you would need a DC to DC charger, # 331-BCDC1240D, but it is expensive...at the same time, it won't leave you stranded.
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 >
Breakaway Kit Replacement 12 V Battery
- Accessories and Parts
- Trailer Breakaway Kit
- 12V Battery
- Hopkins
more information >
Roadmaster Hy-Power Diode - (Qty 1)
- Accessories and Parts
- Tow Bar Wiring
- Diodes
- Roadmaster
more information >
Product Page this Question was Asked From
Hopkins Quick-Lock Diode for Towed Vehicles - Qty 1
- Accessories and Parts
- Tow Bar Wiring
- Diodes
- Hopkins
more information >
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