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Discussion Starter · #1 ·
I'm on my 2nd wire to my elec fan. Its a ford contour 2spd electric fan. 40amp relay. Direct power wire from junction box 8in long of a heavy gauge.

My first power wire had an inline fuse block, and that thing just melted to a goop and caught on a tiny fire.

2nd i just put straight wire, and that melted and broke at the little female blade terminal to the relay and looked corroded all greenish (brand new wire!).

Whats going on??? Bad ground?? The relay gets pretty warm also, and i just replaced it for ghits and siggles.
 

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heavy gauge means anything

what gauge are you running SPECIFICALLY.
 

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Discussion Starter · #3 ·
i dont know the number off the top of my head.. but the corrosion around it worries me. Maybe ill rerun the ground wire to a better spot. Tonight when i get home from work i'll make it out of some HEAVYYYYY gauge wire. Would it be smart to run a fuse, im kinda scared to since my last one didnt pop, the whole fuse holder just melted and got toasty. My local autoparts stores didnt have any fuseable links either
 

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I have the same problem. I have killed two 30 amp relays. I f anyone knows what is causing this please post up. I am running a Spal electric fan.
 

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Dont the contour/taurus fans pull somewhere around 35amps at startup? You need to figure out what "heavy gage wire" you are using as sometimes just because the wire itself is thick doesnt mean its a lower number'd AWG wire.
 

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Discussion Starter · #6 ·
My relays i get are rated at 30amp continuous, and 40amp max spike. The relays get hot but never break. Its the main feed wire going into the relay that always gets toasted.
 

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Make sure you runt he proper gauge wire for the distance the wire is running. For the application I would run at least 12 gauge. And as always I prefer to solder over any other connection.
 

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30 amps

12 AWG minimum and 10 AWG to be safe.

I would do dual relays each one feed ONE fan. not one relay to two fans.
 

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why dont you get an ammeter (or DVOM with amp function) and actually test the amperage being pulled through that wire then base your wiring around that... that is the proper way to do it
 

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SupraDupaFlyBoy said:
why dont you get an ammeter (or DVOM with amp function) and actually test the amperage being pulled through that wire then base your wiring around that... that is the proper way to do it
I don't think that any DVOM out there is capable of measuring current inline( series) use a current clamp so you won't damage your DVOM. I think that either your corrosion maybe the problem or the fan itself. If your fan motors are worn and the bushing is worn and making the fan shift and create a mechanical resistance , your current requirement will go up. Sometimes even spinning the motors by hand will show no resistance until the fan gets moving and shifts fore-aft and creates internal drag.

If your fan takes a lot of current to get it going I suggest a power cap on the relay main power wire. That helps spin start the fan with ease and reduce current requirement as the voltage is held high.

-Joe
 

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figgie said:
30 amps

12 AWG minimum and 10 AWG to be safe.

I would do dual relays each one feed ONE fan. not one relay to two fans.

This is what I had to do with my Flex-A-Lite fans after I went through 3 inline 30amps fuses and fuse holders. Everything completely melted.

There have been no problems so far after I wired up each fan independently.
 

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carchitect, most DVOMs can measure amperage inline but only up to 10amps, obviously you would need to use the ampclamp...

VJ RC51, check amperage first and we can work from there
 

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carchitect said:
I don't think that any DVOM out there is capable of measuring current inline( series) use a current clamp so you won't damage your DVOM. I think that either your corrosion maybe the problem or the fan itself. If your fan motors are worn and the bushing is worn and making the fan shift and create a mechanical resistance , your current requirement will go up. Sometimes even spinning the motors by hand will show no resistance until the fan gets moving and shifts fore-aft and creates internal drag.

If your fan takes a lot of current to get it going I suggest a power cap on the relay main power wire. That helps spin start the fan with ease and reduce current requirement as the voltage is held high.

-Joe
carchitect is right, I would check all your connections and then the fan motors. Clean off everything. Make sure you have good connections everywhere!!! If its still a no go, then go to pick up a motor or whole fan and see if it solves your problem. It really doesn't sound like your wiring. Make sure the ground from the relay box is good too.
 

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figgie said:
30 amps

12 AWG minimum and 10 AWG to be safe.

I would do dual relays each one feed ONE fan. not one relay to two fans.

I recently had a similar issue with my dual zirgos. I was using 1 relay and the inline fuse popped and I overheated. Figgie hit it on the head.

-run 1 relay per fan
-run a min of 10 gauge main power wire to each fan relay from the battery (i.e. one 10 gauge main power wire per relay/fan)
-instead of using an inline fuse on the power wire , I used a blade type circuit breaker that is automatically reset if it trips. It plugs right in to the existing fuse holder. Safer than a fuse. SF member (mike91t) suggested this idea.

Ensure that you use all new wires, relays and fuses/breakers. Also you must ensure clean connections. A dirty connection can also lead to burned wires and blown fuses. I was told dirty connections can actually draw more current thus causing things to burn.

After I added the second relay and a separate power wire to each relay from the battery with the inline breakers. I have had nil issues. :bigthumb:

http://www.supraforums.com/forum/showthread.php?t=374869

Danny
 

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Discussion Starter · #15 ·
i replaced the wire today with a 10awg wire, lets see how it tolds up
 
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