This isn't Alan either .... but
YES you answered your own question.
Follow every above answer.
When you have a fan that runs off a thermostat and the engine finally comes up to temperature-HOT. The thermostat triggers the fan to ON.
the current draw is pretty high @ start-up so running two relays, spreads the current to two different relays lessing the possible failure if you only run one relay. When a fan is running the current draw is greatly lessened. About the last thing you want on a hot day is your fan not working cause you could not afford two relays and the one stops working. relays cost about $6.00, that includes the socket too. They're
cheap and fairly easy to wire. sure beats a single 30 amp fuse.
DON'T run a fuse for this purpose! :hammering:
also consider using a fusable link that gets wired to the relay power source post #30. a roll of it runs about 6 bucks @ FLAPS and is 25 feet worth.
Fusable links should be 4 wire sizes (gauge) smaller than the circuit wire gauge you run for any circuit. solderless but soldered connections and heat shrink all terminals.
I run on my 51, 6 relays for various power using operations and have an additional multitude of fused circuits.
18ga. Fusible Link protects 14ga. or heavier wired systems
16ga. Fusible Link protects 12ga. or heavier wired systems
14ga. Fusible Link protects 10ga. or heavier wired systems
12ga. Fusible Link protects 8ga. or heavier wired systems
you can buy fusible link wire in bulk @ most any FLAPS and if you intend on doing a whole wire harness or have several projects going it's really cheap to buy bulk.
TRY:
A LOT of Information here...
http://www.madelectrical.com/catalog/rly-1.shtml relay kit :
http://www.madelectrical.com/catalog/rly-1.shtml http://www.madelectrical.com/catalog/fusible-link.shtml http://www.madelectrical.com/catalog/cn-1.shtml I highly suggest this.
my.02 :p
