Ditch light wiring help

I have two LED ditch lights that I need to wire up tonight. Can I wire them in series? They're only 18 watts so I'm going to run them through my 25 amp switch for now.

My thought was to wire from battery negative to a fuse holder, to pod #1, to pod #2, to the switch, then to battery positive. Does that sound right?

 

So you're putting the fuse on the negative side? That's usually donee not the positive. Other than that it sounds ok... Remember though that watts and amps aren't the same, what's the rating on your switch?

 

Your 25 amp switch is way over kill. 18 watts at 13.5 volts equates to 1.33 amps of draw and at 14 volts it's less, 1.28 amps of draw. These values are per light.

Best way in my opinion is running power to a relay and using a small current charge to switch on the main power to the lights after going through a 7 amp fuse.
5 amps may also be sufficient but over the years corrosion may play a role in increasing the resistance value and increasing amp draw.

Your best bet is wiring both lights in parallel (each having its own power lead). That way when one dies the other can still operate.

 

I'd get a 4 pin or weatherproof 5 pin relay and base.

On post 30: will be supply voltage from battery to the relay. (7 amp fuse before the relay to protect both the relay and lights).
Post 87: power out to lights from the relay.
Post 87A: Unused.
Post 86: low amp supply from in Cab fuse box behind cubby hole on lower drivers side dash to switch to the relay.
Post 85: to body ground from the relay.

Power in automotive applications goes positive to negative(ground).

Hope that helps bud.

 

I decided to pick up a relay and do it right the first time. How do you suggest I split the wires coming from the relay?

 

??

 

Best way is to solder the wires, the less connections the better. That means strip the ends off of the wires going to the lights, twist them together as one, slide on heat shrink tubing, then solder them to the relay terminal and slide the heat shrink down to cover the connection. Sorry for the long wait for a reply, forgot to hit "post reply" button

 

do not wire them in series, eventhough they arent like an incandescent, you still get voltage drop. meaning the farther down the line you go, the dimmer they will get.

they need to be wired in parallel.

 

Thanks guys. I'm in the process of wiring them per 2.7taco's instructions in parallel.

 

Series circuits will have a voltage drop across each load.

The lights get wired in parallel to the hot and the ground so they get the 12 volts to each. The switch gets wired in series with the hot and the fuse feeding the switch.

I wouldn't solder to the relay personally, insulated sta-kons and dielectric grease will keep any corrosion out. I'd also just twist the wires feeding the lights and put them into a sta-kon.

Connecting to the lights themselves, I'd use a 2 pin connector similar to a 4 wire trailer connector soldered and shrink tubed. Individually and overall. You will see that one red wire has the pin exposed, attach that half to the light. Stagger the solder joints, so that it doesn't look too pregnant. Use #18 gauge appliance,"zip" cord. Now look at and feel the cord; one side will have ridges or maybe a squared corner. In the electrical trade, "the grounded circuit conductor," must be identified, and that's how they do it. Here, it's an easy way to keep track of the wires without labeling each and every one.

Use an add a fuse. Fuses are not there to protect what you're connecting to them as much as they are to protect the wires from over heating and breaking down the insulation.

On that note, if you decide to forgo or do something different... The following is a true story I'm so glad it wasn't me. Going back a few years, a friend bought a new car and about 1200 watts of amps, speakers, head unit. Nakamichi, a/d/s, Alpine, he spent a chunk of change. He had everything but the fuse blocks and was in a hurry to get his car back together and hear his new toy. He didn't think anything of the sparks when he vise gripped the wires for the amps to the positive battery terminal. When he put the back seats back in, he pinched the wires. When he climbed in, he smelled something burning.The wires were burning through the rug and back seat. Nice black lines where he ran the wires along the drive shaft hump.

Don't forget the fuse! 5 amp for those light will be plenty.

Be cool, be safe, good luck and enjoy the final product.