I am running 5 100v off road lights, it doesnt tell me the amps they take. What size wire and inline fuse should i be using? thanks
country

 

5 100 watt I assume?

If we figure they will be running on 12 volts, 100 divided by 12 = 8.3 amps each. 5 x 8.3 = 41.6 amps.

The commonly found relays for foglamps and such are rated at 30 amps. So you need to buy two, and put three lamps on one relay and 2 lamps on the other.

Also a common wire size that is easy to find is 10 gauge. In household rules it's rated for 30 amps also, so you could run two 10 guage wires up to the lights, with one feeding two and the other feeding three lamps, in conjunction with the two relays.

You could also run two seperate fuses rated at 30 amps. Each of these would feed one of the two relays.

You could install one heavy circuit, with a large fuse, large wire, and a large relay, but it may be cheaper and easier to run the two smaller circuits.

 

Dito on the two relays and with separate circuits. Not only will be easier to put together, but easier to trouble shoot in the event of problems. Ebay has great deals on wiring and relays if you take the time to look. Depending on what you are going to be in the end, you might consider a fuse block of some type for adding accessories down the road, like 12V sources front and rear for compressors and such.

 

I"m not good with electrical so thanks for the help. I plan on throwing in a 12,000lb winch this summer too so i was going to run a dual battery. Wondering how this would change the lighting setup if any, and do i just link the two together or how do i do that; will i have to change my alternator.
thanks

 

For the best setup, I would get a battery isolator, and a deep cycle battery. Your stock alternator should hold up to this.

The second deep cycle battery will run the winch, and anything else you want to run, but keep seperate from the original starting battery.

The isolator will let the deep cycle battery be charged by the alternator, but not let the starting battery be discharged by any loads on the deep cycle battery. So if you run the winch, lights, radio, etc. off the deep cycle, with the engine off, and you run the deep cycle down, the starting battery will be unaffected and still be able to start the engine.

A deep cycle type battery will be required if you do foresee running the second battery way down in charge. A regular battery will not hold up to repeated deep discharges.

So, you can run your lighting either way. To the regular battery if you plan to use them only when the engine is running, or to the deep cycle second battery if you want to run them very long with the engine off.

 

Thanks for all the help on this one. What size isolator would you think about running? thanks

 

I am running a 160A isolater, and have a 110A alternator. So I have a buffer of 50As, so to say. the key is to have a larger isolator than alternator output. I went as far to add a fan to the isolator, as I plan on using it to charge trailer battery in the summer, truck would be at idle when doing this, I want as much air flow to keep it cooler. I found mine on ebay. SurePower

 

Here is a site you can go to for calculating wire size. Scroll down past the chart and you can enter in your info, and it will tell you the characteristics. With 10guage wire, you will experience a 1.1 voltage drop at 15 feet of wire, taking you down from 12VDC to 10.9, which isn't really bad, that should work great. Considering you have about 13.8VDC or so from the alternator, you will still have a good 12VDC at the lights to give you good light.


SITE: http://www.powerstream.com/Wire_Size.htm

 

"ISOLATOR"?

What the heck is that?

its a DC circuit - you can't use a transformer....

You guys just got ME lost, and i've been playing with electricity for twenty two years.

 

A transformer is simply two coils of wire up against each other. Each coil is just like a home made electromagnet, wrapping wire around a nail. This will work with DC or AC. For example, my waterproof razor uses this principle to charge its battery without using contacts on the charger, it just sits up againts it. The razor does not have an AC-DC converter circuit inside, it just uses inductive coupling to charge the battery.

my .02.

 

Commonly called an ISOLATOR, is basically a two diode setup, passes DC current in one direction allowing the charging two batteries, but not allowing each battery to be connected in parallel, isolating the two, hence the common name of ISOLATOR. Check outSure Power their website can explain it all better than I can.

 

Keep in mind with most isolators; they do use diodes which means a little voltage drop. Not much of a problem in most cases, unless your alternator is getting kind of weak or you have dry cell batteries, where fully overcoming the internal resistence of the battery is critical for long life.

Stop by a good RV shop sometime. They usually have a few different types to look at.

 

Also with the diode voltage drop, if you take the sense wire for the voltage regulator and connect it down stream of the diodes, most alternators will make up the difference and voltage loss will be very minimal.

 

[QUOTE=Greywolf]"ISOLATOR"?

What the heck is that?

It's just diodes and heatsinks. Allows the alt to charge both batteries. The two batteries cannot share circuits.