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Discussion Starter #1
Anybody know whats up with this setup? Also I am going to be running 2 fans. Im not good with electrical stuff and I am not sure how to go about wiring 2 fans up? I am thinking I should use a butt connector for the positive on the fan to the battery and a butt connector for the negative. Then I should use 2 of those wire tap connectors to connect the second fan to the positive and the negative? Then both fans will have power and ground correct? Each of my Spal 12" fans is rated to draw 7amps so 14 total. That should be safe with this controller?


Also Why would they have it wired like this? Does not make sense to me. I am not sure why they have the red wire on the controller itself hooked to the ground wire on the fan? I have never seen a fuse in a negative wire before. I can picture in my head how this works but it seems they could have done this an easier way.

I am open to any thoughts or suggestions. I need to get this hooked up tomorrow.





 

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I don't blame you for being confused. I am confused also.

My 12" SPAL fans are rated to draw 16-22 amps EACH. 30 amp fuses for each fan recommended. Where did you get those magical low amp fans. Pull the spec sheet from the SPAL site and double check the amperage draw.

The fuse on the ground side is not usual. Normally you want to protect everything from the hot side down. I guess they are thinking the fans are insulated and no chance of shorting out against frame/metal, just internal melt down so the fuse would work anywhere. At least it protects their controller.

I don't believe a controller can run 2 SPAL fans without using additional individual 30 amp+ relays for each fan to handle the current load. Use the controller to run the control circuit for both relays, then it should survive. This is what is normally done when you have 2 fans to control.
 

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The engineer was probably a Brit, and was raised on positive ground systems.

Put the fuse in the hot wire if it makes you feel better. I know I would.

Forget the tap splice. Use a yellow butt splice and splice both wires in at once.
You'll need to fold over the feed wire so it will fit better in the yellow butt splice, else cut one of the fan wires long, and feed it all the way through.

the key to making good crimp connections is having a GOOD crimping tool. If you are planning to use one of those cheezy combination stripper/crimper tools that comes in a $12 splice kit, DON'T. Throw it in the trash, cause that is what it is worth. Get yourself a good ratcheting crimper ( and take the dam ratchet out ). Lots of good ones out there, but if you want the best, get a LOBSTER.

http://www.hellermanntyton.co.za/productpdf/Tools_Catalogue_2006_p3.pdf

I recommend the AK-15. It says for uninsulated connectors, but it works fine with insulated as well.
 

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Discussion Starter #4
I don't blame you for being confused. I am confused also.

My 12" SPAL fans are rated to draw 16-22 amps EACH. 30 amp fuses for each fan recommended. Where did you get those magical low amp fans. Pull the spec sheet from the SPAL site and double check the amperage draw.

The fuse on the ground side is not usual. Normally you want to protect everything from the hot side down. I guess they are thinking the fans are insulated and no chance of shorting out against frame/metal, just internal melt down so the fuse would work anywhere. At least it protects their controller.

I don't believe a controller can run 2 SPAL fans without using additional individual 30 amp+ relays for each fan to handle the current load. Use the controller to run the control circuit for both relays, then it should survive. This is what is normally done when you have 2 fans to control.


The place i bought them said 7 amps each. I looked here on the spal spec sheet but I cant figure it out?

http://www.spalusa.com/pdf/30101522_SPEC.PDF#view=FitH
 

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Discussion Starter #5
The engineer was probably a Brit, and was raised on positive ground systems.

Put the fuse in the hot wire if it makes you feel better. I know I would.

Forget the tap splice. Use a yellow butt splice and splice both wires in at once.
You'll need to fold over the feed wire so it will fit better in the yellow butt splice, else cut one of the fan wires long, and feed it all the way through.

the key to making good crimp connections is having a GOOD crimping tool. If you are planning to use one of those cheezy combination stripper/crimper tools that comes in a $12 splice kit, DON'T. Throw it in the trash, cause that is what it is worth. Get yourself a good ratcheting crimper ( and take the dam ratchet out ). Lots of good ones out there, but if you want the best, get a LOBSTER.

http://www.hellermanntyton.co.za/productpdf/Tools_Catalogue_2006_p3.pdf

I recommend the AK-15. It says for uninsulated connectors, but it works fine with insulated as well.


I think I will do what you suggested here. Thats a must more secure connection. :yes:
 

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Discussion Starter #6
It works!!!!!! I am surprised at the amount of air these little Spal fans pull. Stick your hand way at the back of the engine and you can feel strong hot air blowing on your hand.
 

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The place i bought them said 7 amps each. I looked here on the spal spec sheet but I cant figure it out?

http://www.spalusa.com/pdf/30101522_SPEC.PDF#view=FitH
The way I read it is 12.4-13.6 amps depending on airflow and resistance per fan. Humidity, Air Pressure and wind change the resistance. Tested with 13v source. The car will vary from 12.5 to 14.x volts. More volts usually means a little more RPM and amperage pushed through.

That means 2 fans can pull up to 27.2 amps possibly a little more. That is above the MAX 25 amps for one controller they list. It may work, but you don't have much if any safety margin.

I would add another relay to control the second fan. You could use the fan controller for one fan. The fan controller could also be wired into the control circuit of the second relay thus running a fan and second relay control circuit together. One controller, one extra relay, both fans.

Here is a quick diagram of what I am talking about. Any electrical gurus want to approve this logic? When the controller is in FAN OFF, both sides of the 2nd relay will be getting positive volts no energizing the circuit for the relay, 2nd fan off also. Once the controller turns the fan on, or grounds the fan, then the ground for the relay will work since there is now a ground for it also. 2nd relay energized, 2nd fan on also.
 
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