Relay wiring

[aldive]

A friend asked me how to wire a five terminal 12 v relay to turn on an accessory. What wires go to which of the terminals?

Help, please.

 

[CAHUNTERMAN]

Here is a list of the connections to a standard Bosh type accessory relay. The coil is powered by a switch or whatever device you don't want the high current being drawn from. Typically the common would go to your +12 fused line and the NO or NC contact will send the +12 to whatever accessory you are powering. Somewhere I have a drawing that shows this better. If you need that let me know and I'll try to dig it up.

12v Bosh relay

Terminal Circuit
85 COIL
86 COIL
30 COMMON
87 NO
87a NC

 

[aldive]

I am not an electronics wiz ( or even close ).

Can you explain this in a more simple way? In other words, what wires go to what terminal.

Thanks a lot.

 

[CAHUNTERMAN]

On a Bosh 12v accessory relay the 5 terminals are numbered on the plastic next to the terminal. If you are wiring say some KC lights with a switch in the dash to turn them on you would connect as follows:

Terminal #85 wire to ground.
Terminal #86 wire to one side of dash switch, other side of dash switch to a fused +12 line.
Terminal #30 wire directly to battery +12. Be sure to install a fuse close to the battery and use wire large enough to power the lights.
Terminal #87 wire directly to lights with same size wire as #30.
Connect grounds to the lights and they should come on when the dash switch it turned on but they will be drawing their power directly from the battery through the relay.

Hope that helps.

 

[aldive]

You the man; exactly what I needed.

Thanks so much.