Wiring lights directly to battery circuit.

[RidgeHiker]

I was considering hooking my work lights into an existing circuit which I discussed on another thread and have decided on another approach.

I want to run them more directly off the battery with an in-line fuse.

My question is where is the best place to connect in to? If I understood what I was seeing, it looks like the positive lead from the battery goes to the solenoid on the starter and a hot lead goes up to the main key/starter switch. Is it OK to connect in to either of those? Is there a better place?

The alternator is 35 amps. The most I would have on the circuit is three 55 watt halogens (13.75 amps). I could go to three 35 watt HIDs but they are more expensive and I would have to order online. One thing I noticed with HIDs is the start up draw can be double.

 

[RoyJackson]

I'm not sure if wiring lights directly to the battery is a good idea...however, when I installed a 12 volt outlet to my 4400, I talked to one of my local Deere dealer's technicians. He recommended hooking the hot (power) wire to the battery with an inline fusible link and the ground to the battery's ground.
Now, my 12v outlet is (primarily) for a flashing warning light that draws no more then a few amps. As a flashing light, it's pretty unlikely I'd leave it on when I'm not on the tractor.

So, yes you can...just make sure you turn those lights off!!!

BTW, I used 14 gage wire and crimped all connections. If you have a soldering iron, that might be better, but crimping does work well too (I didn't have a soldering gun and didn't want to buy one...not for a one time use). Although I used 14 gage wire, I suggest you use 12 gage (and I wish I had done so). I also ran the wires in a protective sheathing (buy it at any car parts store) and I suggest you do that too. Once you get to the operator's platform, you can determine the best routing to your ROPS (which is where I assume you'll mount the lights).
For neatness, I ran my wiring along side the stock wiring harness and wiretied every 10-12 inches.

Have you considered where you'll put the switch or switches?

 

[D7E]

All our tractors/combines have up to 6 extra worklights on them many are 100watt works just fine off the battery with a fuse .

 

[SpringHollow]

12 volt blade fuse holders are cheap (they also have 12V circuit breakers). I have hooked up several directly to my battery but I also use a 12 volt relay to "enable" those circuits. The relay is connected to a circuit off of the key circuit so the lights etc can only be on when the key is on. This keeps you from draining your battery but at the same time prevents you from overloading the key circuits as well. IN my opinion, this is the best way to add most circuits.

Also, I really like the LED lights I have much better than halogen lights - brighter, whiter, and draw much less current.

Ken

 

[CharlieS]

Wire size is dependant on total amp draw of the accessories added. If you are going to connect all three lights to one circuit/switch then #12 wire would be appropriate. The formula for computing a circuit load is derate to 80% of maximum allowable amperage for a given wire size. #12 is good for 20 amps x 80% = 16 amps. Similarly, #14 wire is 15 amp rated thus is capable of carrying a continuous load of 12 amps. The key word here is continuous load which is defined as 30 minutes or longer.

The only drawback to connecting any accessory directly to battery power is battery drain should it be left on or turned on accidently. The best place in this case to pick up power would be directly at the + battery terminal, with an inline fuse as close to the battery as possible, a 15 amp fuse should carry the load, though a 20 would be permissable also.
and be sure to use a switch rated higher than the total output of the load. In this case, a minimum 15 amp rated switch, 20 would give more of a safety margin.
The other possibility is run the lighting through a relay, allowing for a lighter duty switch and smaller wire to the switch, as it only controls the small relay instead of the higher amp loads the lighting will require. The main advantage of using a relay is usually shorter runs of heavier wire, (depending on lighting location) which helps guarantee full current to the lights. In this case wiring would be from power supply/fuse/relay to the lights on the high amp side. By using the relay you could pick up switch power at any convient location using smaller wire, say the switched hot side of an ignition switch, offering the safety margin of lighting would turn off with the switch off. Amp or wattage draw on the switch side of the relay would be almost non existant.

 

[oldnslo]

If you are going to be adding more features in the future you can also purchase fuse blocks that are meant for adding circuits on equipment. These are nice since you now only have added one extra lead to your battery terminals Vs ...

Would also use a relay like others have said.

One example of what I am talking about can be seen at Welcome to Cyclenutz - Motorcycle Accessories for people who are NUTZ about Motorcycles

 

[RidgeHiker]

Is this how the relay works? I assume the power supply feeds into the relay and from the relay directly to the lights. A separate circuit would go from the relay to the switch and back to trigger the relay. Is this correct?

If the above is correct I guess I could do it 2 ways - does this make sense?:
1. Switch the relay from the main key switch and have an on/off switch in line to the lights from the relay. The lights would not stay on with the key off.
2. Switch the relay with an on/off switch which would permit the lights to be on with the key off.

 

[JoeL4330]

relay works as you describe; depending on where your lights will be, you can simply trigger the relay from one of your existing headlights (which is near the battery)...bring load power to the relay through a fuse or circuit breaker...I've frequently just hot-glued the relay (and the circuit breaker) to the top of the battery case. As stated, I'd use 12ga wire.

 

[RidgeHiker]

Our battery is not easy to access so we may need to take off somewhere else. If we are able to access it what is the easiest way to hook in. Do you pull the clamp bolt and put a contact in?

 

[JoeL4330]

For the hot (red, +) use a ring terminal on the bolt that tightens the clamp;

[for the ground (black, -) you can attach to any good chassis ground (see where your black/- battery cable goes.]

you can make up by crimping ring terminal onto inline fuse like:

In-Line Fuse Holders

Any auto parts store should be able to help you