Switch Installation Question

[TJim]

For example, like this quick little diagram I just made: (sorry for the quality)

The relays on the right will be in my AUX PDC, and they will power the accessories. (There will be 5-7 Relays between 20-60A)

I want to add the relay before the switches in order to be able to turn on the switches only when the KEY is ON.

 

[jesseshoots]

For example, like this quick little diagram I just made: (sorry for the quality)
View attachment 151649

The relays on the right will be in my AUX PDC, and they will power the accessories. (There will be 5-7 Relays between 20-60A)

I want to add the relay before the switches in order to be able to turn on the switches only when the KEY is ON.

That will work perfectly. Just make sure to fuse the power coming into the 5-7 relays shown on right before going to the desired device.

 

[TJim]

That will work perfectly. Just make sure to fuse the power coming into the 5-7 relays shown on right before going to the desired device.

Thanks!

Yes, for sure I will fuse the power coming into the relays on the right (#30pin). I just didn't sketch the wiring for those relays on the diagram to be a little less confusing.

 

[Feralkid]

The fuse should be placed BEFORE the relay/solenoid. This diagram is incorrect in that regard.

The concept is to prevent arcing by cutting the circuit as the fuse blows if the wire insulation becomes damaged and the conductor touches ground. The fuse should be as close to the power source as reasonable. Usually within 10 inches.

Everything before the fuse is unprotected against current overload, so you want that piece of wire to be short.

 

[TJim]

The fuse should be placed BEFORE the relay/solenoid. This diagram is incorrect in that regard.

The concept is to prevent arcing by cutting the circuit as the fuse blows if the wire insulation becomes damaged and the conductor touches ground. The fuse should be as close to the power source as reasonable. Usually within 10 inches.

Everything before the fuse is unprotected against current overload, so you want that piece of wire to be short.

You are correct!

My diagram is incorrect as I should be place a fuse before the relay on the left. I did not do it because I was focused on the switches side, and I did the diagram in a hurry.

It goes without saying that I will place a fuse before each #30 pin of each relay.

My question though is whether I should place a fuse before each switch too (in a switch panel), or I could "bridge" the switches with just one fuse (as shown in diagram).

Diagram: (Fuse placed before every #30 pin of every single relay - not shown in diagram)