Spike Relay Wire Gauge

I am wiring up some Spike relays to control solenoids for our “apparatus”. I don’t want to waste a bunch of 14 gauge wire to do this, and I was wondering If I can put like a 5 amp fuse in the fuse block or in the relay where the 20 amp regularly is.

I have black and red 24 Gauge wire to use. What type of fuse would I have to put in for that?

The answer is, you must follow the wiring rules. So NO on a 5 A fuse/breaker.

As for what fuse, you need to keep the 20A fuse in the Spike and use a 20A breaker in the panel.

(And, this may sound silly, but you should read Section 8.3.6. It has all the wiring rules.)

So how do I hook up 14 gauge wire to the festo valves with the stress relief and tiny little screw terminals?

Ok, I promise I read the rules several times before but…

<R74> …24 AWG or larger diameter wire must be used for providing power to pneumatic valves.

Do I just use the 20 amp fuse and not worry about it?

You should use 18 AWG or larger from the breaker panel to the Spike and 24 AWG from there to the solenoid. That way, you’re fulfilling both parts of the rule.

<R47> All main and branch circuits shall be wired with appropriately sized wire:
 12 AWG or largerdiameter wire must be used for all circuits protected by a 40A circuit
breaker.
 14 AWG or largerdiameter wire must be used for all circuits protected by a 30A circuit
breaker.
 18 AWG or largerdiameter wire must be used for all circuits protected by a 20A circuit
breaker.
 24 AWG or larger diameter wire must be used for providing power to pneumatic valves.

Yep. The 20A fuse is protected by a 20A breaker.

The 20 amp fuse in the Spike is meant to protect the Spike itself from damage; the 20 amp breaker in the panel is meant to protect the (18 AWG) wiring from overheating.

The Spike must be fed by a 20 amp circuit breaker per R55 and Team Update 9. The robot rules state that wiring protected by a 20 circuit breaker be #18 or larger. So the Spike is fed with a #18 but can have #24 or larger wire on the output if the load is a pneumatic valve(s). The fuse in the Spike will blow open in the event of a wiring short on the output of the Spike.