add-a-circuit kit for LED lights

[kubotacory]

Does anyone have experience/issues with using an Add-A-Circuit kit for additional wiring on your tractor? I have a Kubota B7800 with the dynamo instead of the alternator and want to add work lights. I've taken in to consideration that the dynamo only produces approx. 14 amps and with that have decided to spend the extra $$ and go LED work lights. I plan to replace my current headlight bulbs with LED's as well to free up space, perhaps some taillights too if need be. I'm looking to put four 18W work lights on one circuit with a total of 4.24 Amps draw. I also want to have the lights powered from a switch so figured it best to keep them on their own circuit rather than splicing into an existing. A thought was to use one of the ATO Add-A-Circuit kits to tap into an existing fuse slot. Can anybody provide any advise on this?

 

[k0ua]

Re: add-a-circuit

Does anyone have experience/issues with using an Add-A-Circuit kit for additional wiring on your tractor? I have a Kubota B7800 with the dynamo instead of the alternator and want to add work lights. I've taken in to consideration that the dynamo only produces approx. 14 amps and with that have decided to spend the extra $$ and go LED work lights. I plan to replace my current headlight bulbs with LED's as well to free up space, perhaps some taillights too if need be. I'm looking to put four 18W work lights on one circuit with a total of 4.24 Amps draw. A thought was to use one of the ATO Add-A-Circuit kits to tap into an existing fuse slot. Can anybody provide any advise on this?

Not only do I not have any experience with it, I have some reservations with it. A fuse is to protect the wiring from and overload that would raise the temperature of the wire and lead to a fire. So for a given wire size in the harness there is an applicable fuse size that will overheat and open the fuze element before the wire overheats. I am thinking that the manufacture puts that size fuze in the slot to begin with. Now if you put an add on device like this on AND if you put two fuzes in it that are the same rating of the original fuze than you are going to be in trouble. Now if you had an original 10 amp fuse lets say and you put this device on and stocked it with two 5 amp fuzes in it to have 2 circuits that are fuzed at 5 amps each, then I would say you would be OK.. My point is do not exceed the original current draw that was spec'd for the wiring harness. I applaud your idea of replacing the incandescent bulbs with LED's especially given your low generating ability.

James K0UA

 

[kf4uda]

I looked up a datasheet on one of these. This particular one is from Littlefuse:

"Extension board for an additional fuse protected tap from an
existing MINI size socket. The 2 fuses for the existing and the
new circuit are oriented horizontally."

It looks like one fuse is for the original circuit. The other fuse is for the added circuit and is fused independent of the original.

Edit: Forgot to add that the maximum fuse rating on this one is 10 amp.

 

[kubotacory]

Re: add-a-circuit

Thanks James. I understand the point of not exceeding the original current draw specified for the circuit. Until a few days ago I was unaware that these add-a-circuit kits existed and I haven't had much luck finding detailed instructions on their usage. I was surprised that the little 1156 existing incandescent headlight bulbs draw 2.1 amps each. The replacement 1156 LED 360 degree bulbs I found only draw a mere 290 mAmps each - big difference. I haven't pulled any of the tail light bulbs out to see what they are yet but figured if I replace more bulbs with LED I could possible free up enough on an existing circuit to utilize the add-a-circuit without any fears of overloading. My existing set up has a 20A blade fuse for work light. I haven't tested it all yet but I believe this 20A currently powers the rear lights (tail, turn signals, hazards) with an optional tail for an add on. I thought about just using the provided tail but not sure I could put my work lights on a switch at the instrument panel as desired.

 

[kubotacory]

Re: add-a-circuit

Thanks Chris. I found that same datasheet from Littelfuse before posting here. I would need the ATO style vs. the MINI style but the maximum fuse rating is the same, 10 amp. I thought too that the added circuit would be independent. I'm not entirely familiar with wiring on 12V systems so I didn't want to make wrong assumptions and mess up an existing circuit.

 

[s219]

There should be an extra unused "work light" circuit with wiring that runs to the right rear fender. It will have its own slot in the fuse box already. At least that's the case on my B2920.

 

[kubotacory]

Attached is the diagram for the B7800. It has a work light circuit which may be unused. I haven't tested it yet, but suppose I need to.
Like most things I tend to do, I'm probably over thinking this whole wiring scheme. I just want to do it right the first time.

 

[msb1766]

I think you would be better off using a relay. Here is is a really good explination of how a relay works and a diagram of how to wire a relay.
Relays - How to Wire - YouTube

http://www.offroaders.com/info/tech-corner/reading/relay-diagram.gif

 

[kubotacory]

Thanks for everybody's helpful advise. I picked up a new continuity tester on my way home from work today (old one broke). It appears the existing 20A work light fuse is unused so the add-a-circuit is not needed after all. The wiring for this that runs to the rear fender appeared to be pigtailed in with the tail light circuit which confused me. I bought my tractor used so not sure if that's how it came factory or if wires were re-bundled at some point. Good thing is I do have an easy tap in source on a dedicated unused circuit. Now it appears to be just a matter of where to best locate a switch, and replacing some other bulbs with LED's to keep the overall amp draw at a minimum.

 

[k0ua]

Thanks for everybody's helpful advise. I picked up a new continuity tester on my way home from work today (old one broke). It appears the existing 20A work light fuse is unused so the add-a-circuit is not needed after all. The wiring for this that runs to the rear fender appeared to be pigtailed in with the tail light circuit which confused me. I bought my tractor used so not sure if that's how it came factory or if wires were re-bundled at some point. Good thing is I do have an easy tap in source on a dedicated unused circuit. Now it appears to be just a matter of where to best locate a switch, and replacing some other bulbs with LED's to keep the overall amp draw at a minimum.

Sounds like you are well on your way. Good luck with the install.

James K0UA