Adding Work Lights Question

[Tractor Tom]

Can anyone explain to me why a relay switch is needed or used when hooking up more then a couple of work lights? I guess I’m not sure what a relay switch does?? I have two lights on the rear of my CK20 wired without a relay, and would like too add two on the front as well. Thanks for the help.

 

[kennyd]

Relays are used to handle high current. The automotive style relays I use are rated at 30 amps. Most switches are only rated at about 10 amps or so, and some of the nice looking small ones are only rated at about 5 amps. The use of the relay also allows you to run lighter gauge wire up to the switch because you are only switching the relay, not the current draw of all the lights.
If you have two 50 watt lights, then your are pulling about 8 amps.

 

[Highbeam]

The relay allows your dash switch to only use a small amount of current to throw a bigger switch in the relay which connects the larger current load of your lights. Without a relay, the dash switch would be passing the full current to the lights and would melt. Also a relay allows you to pull the huge current for the lights right from the battery instead of a dash circuit.

 

[Iowachild]

. Also a relay allows you to pull the huge current for the lights right from the battery instead of a dash circuit.

You still want to add an in-line fuse to protect the wiring and relay. If your relay contacts are rated at 30 amps and you run #10 AWG wire you can fuse for a max of 30 amps.

 

[Tractor Tom]

Thanks for the replies, I now have a better understanding of what a relay does and why I need to use one when hooking up my work lights. Thanks again or the help. This is a great website!!!! If you have a question, you’ll get an answer.