Parts to Connect Trailer Lights to 12V Trailer Battery
Updated 07/03/2019 | Published 07/02/2019 >
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Question:
I have my horse trailer. Currently, I have a few lights thats only working when my truck is pinned the ground is in the hitch and my truck is running. I have a battery in my trailer. I want my light to run with my battery. Can I only take a cable from my battery and connect it to the cable that arrived from my 7-way pinned the cable that give power to my light. Thanks you
asked by: Gabriel F
Expert Reply:
It is easy to wire your trailer battery to your trailer's lights if that is how you prefer to run them. You might want to add a Solar Charger or two, like # PTW2997, to keep a continuous charge going to the trailer battery. This charger will naturally deliver a varying power output to your battery depending on the level of sunlight hitting the panel so using two in parallel connection to the battery will really help maintain its charge. If you need a 12V power switch to control the lights use one like # PK34212 or # PK34308.
To make the most of your available battery power I strongly recommend you use only LED-type lighting which is much more efficient than standard incandescent bulb lights which use about 10 times as much power and which also generate waste heat. If you switch your trailer lights to LEDs you'll have much more operating time for your lights. I linked our page for LED interior trailer lights; some of these have their own built-in power switches. If you use lights with switches you do not need the separate ones listed above.
I also linked our LED type "bulbs" that are available as direct drop-in replacements for many of the popular incandescent bulbs used in RVs. If you'd rather not replace complete lights you may be able to use one of these LED elements. Just match them up to the number on your bulbs.
A trailer-mounted auxiliary battery usually receives a low-level trickle charge through the 12V pins on the vehicle and trailer 7-way connectors. This feed from the vehicle delivers what we call a "maintenance charge"; it is enough power to keep a charged battery topped off but it is not enough power to re-charge a battery that has been depleted from use. The Solar chargers will work well.
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