wire size on relay

[kglowacky]

setting up my relays to the following .

Fans - currently the fans have 12-10 gauge wires coming from it. The fan assembly came off a 2005 Chrysler . I bought 30 amp relays. They came with 14 gauge wire. Do I need to re wire these relays with 12 gauge wire?? If so do I need to rewire the three wires to the bigger gauge and leave the switch wire at the smaller gauge as it will be connected to the ecm small gauge wire.

[mongocanfly]

The small trigger wires going from the relay to the ecm should be fine...but if the fans are 12ga, then that's what I'd use..it really depends on how many amps the fans will pull...use to small a wire and the wires will melt ...

[kglowacky]

thanks that what I thought. Now my next question is are there different size relays or does a basic relay 30 amp handle the bigger wire

Also wondering if I should run a 40 amp fuse in this loop or a 40 amp circuit breaker. Any thoughts?

[pcmcobra]

There are 40 and 50 amp relays even bigger. Fastronix has some
Fuse it at the power going out of relay(s) to fans. Fuse each.
Or clean them wires up and go with the msd solid state relay. 4 channel 50amps each.

[kglowacky]

going to fuse it as you state using 12 gauge all the way to the hook up on the power side and ground side. use smaller gauge on the switch size

[solidaxel]

I had to change 3 of my electric fan relays to a larger relay and a larger wire and for a 12vdc source, I used the Alt. for the supply

The A/C cycles and then the fan cycles and the relays were getting hot and then the connection at the fan was starting to fatigue and then finally, I lost a fan because of low voltage and bad/open connection

The stock relay and wiring harness I am only using for the trigger for the new heavy duty
relays and wire 8 and 10AWG

We will see how this summer goes!