Electric fan wiring issue

[focusedontheprize]

In my '49 I am currently running a 2 speed older Taurus/Sable fan. I am also running a 21 circuit EZ Wiring harness throughout the truck also. The truck is outfitted with LED turn signals and tail lights.

There really isn't much pulling for power on the harness I believe (my uncle is doing the wiring on the truck). Everything is hooked up at the moment except the fan and it seems every time he tries to run the fan he blows a fuse.

How did all of you guys running electric fans hook them up?

[mknittle]

Some of the higher amperage fans run a relay.

[mknittle]

I found this on a Taurus forum

[focusedontheprize]

Originally Posted by mknittle

Some of the higher amperage fans run a relay.

Thanks. Yeah at the moment he has a relay in the loop. He said last night he tested it and when the relay is in the circuit (think that is the proper term) the fan does not work, however when he bypasses the relay the fan works fine.

Also thanks for the diagram, I will send that over to him.

[mknittle]

Originally Posted by focusedontheprize

Thanks. Yeah at the moment he has a relay in the loop. He said last night he tested it and when the relay is in the circuit (think that is the proper term) the fan does not work, however when he bypasses the relay the fan works fine.

Also thanks for the diagram, I will send that over to him.

You're welcome. sometimes you find god info in the strangest places

[Rufton]

I've experienced relay failure; the relay contact developed a white crust. Now I run redundant relays, redundant switches and redundant fuses. Occasionally, I verify both high current circuits are functioning; which reminds me I need to check em.

You probably know a relay can allow a low current circuit to trigger a separate high current fan circuit. I do have fan rated fuses in the high current circuits.

[focusedontheprize]

Originally Posted by Rufton

I've experienced relay failure; the relay contact developed a white crust. Now I run redundant relays, redundant switches and redundant fuses. Occasionally, I verify both high current circuits are functioning; which reminds me I need to check em.

You probably know a relay can allow a low current circuit to trigger a separate high current fan circuit. I do have fan rated fuses in the high current circuits.

Yep. Relay failure it was . Ah Pepboys .

[Rufton]

Originally Posted by focusedontheprize

Yep. Relay failure it was . Ah Pepboys .

Did you dissect it outta curiosity?

[mknittle]

Originally Posted by Rufton

Did you dissect it outta curiosity?

I see I am not the only one that does that

[OKGMC4]

The two speed ford fans really need a hefty relay. They cool great but pull high amps, and that can burn up a small relay quick. If it happens again try a heavier relay.

[focusedontheprize]

Originally Posted by OKGMC4

The two speed ford fans really need a hefty relay. They cool great but pull high amps, and that can burn up a small relay quick. If it happens again try a heavier relay.

Yeah, I was reading about that before. I was talking to my uncle who does electrical engineering and he used a heavy relay on it. He texted me yesterday during lunch time and goes "I am spending my lunch time on this truck" and this man likes a good lunch! Knew it was bothering him.

I told him I wanted to look at it when I was home next week so I will have to see what it is.

[Russell Ashley]

Originally Posted by Rufton

I've experienced relay failure; the relay contact developed a white crust. Now I run redundant relays, redundant switches and redundant fuses. Occasionally, I verify both high current circuits are functioning; which reminds me I need to check em.

You probably know a relay can allow a low current circuit to trigger a separate high current fan circuit. I do have fan rated fuses in the high current circuits.

Rufton, are you powering your fan with two circuits simultaneously or is one a backup that is not used until you switch it on?

[Rufton]

Two completely independent circuits. Relays can run simultaneously or independently. Both circuits are automatic and live. One of those overkill kinda things.