Electric Fan Question - Wiring

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Pumpkinduster

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I am installing dual fans one push one pull.
This is a no brand ebay special to get me by for now. My question is the kit comes with the relay, fans, temp sensor, and a circuit breaker specs below.
My question is I want to eliminate the temp sensor but instead have it kick the fans on as soon as the key is on. I unfortunately have seized plugs on my intake manifold so I just want to go around that.

Wiring
60 Amp Relay
30 Amp Circuit Breaker
30 Amp Inline fuse

The relay has 4 wires
Red with 30 amp inline fuse
Black - Ground
Blue - Fan trigger
White - Temp sensor

Fans - Each
Maximum Fan FAN CFM=2000 CFM
Maximum Fan RPM=2250 RPM
Number of Blades: 10 blades
Thickness=2.5″
12 Volts
6.6 AMP DRAW

So my brain is seeing it connected as battery to 30 amp circuit breaker, Red with inline fuse to circuit breaker
Black to ground source
Blue to fan
White to a ignition switch source? This is what I am looking to figure out if anyone has set up the same please let me know what you used to "trigger" the relay
 
Nut shell

Bat plus to cir brkr.
Cir brkr to relay
Relay to fan
Grounding for fan to good ground.
Feed from ignition like the feed to ignition coil before ballast resister to relay coil
If relay is not internally grounded ground other relay coil terminal.

All this assumes you know which terminals on your relays and cir brkr do
 
Post photos of what you have.

I just reread you post.
 
Found on Google

Rad Fan Relay Wiring.jpg
 
I don't know what your wiring package looks like but consider that a relay normally has 4 parts:
1) Input power - this is the power that it receives and is available to send to a controlled device
2) Output power - this is the power going out from the relay to the actual device being controlled
3) Signal/relay coil Input - this is a 12v wire coming in that will power the coil to close the power contacts
4) Signal/relay coil ground - this is the ground for the coil that is used to close the contacts
In your case, you need to supply the relay with input power (#1) above. Due to the inrush current of electric fans, I would think that you run a wire from your Ign source to the circuit breaker and then to the relay power input. The power output wire (#2) is then sent to the fans to power them up. This output wire is actually protected by the circuit breaker so I don't see a need for an additional fuse. But if you want, you could put the 30A fuse in this output wire.
For the relay coil, run a wire from an Ign source through a smaller fuse (maybe a 10A) to the relay "Signal" input (#3). This wire will really only run less than 0.5A so an 18Ga wire is appropriate. The ground for the relay coil is actually supposed to be the coolant sensor which will ground once the setpoint temp is reached. But since you want to run the fans straight on when the Ign is on, just run this wire to a good ground (#4).
Turning the fans on with Ign means they will run on high anytime the key is On including when the engine is cold or even cranking the car. Not sure you really want that but up to you. I'd suggest running the relay coil power (signal input #3) through a toggle switch so you can flip them on once the engine is warm or after started anyway. But you can't forget or you risk an overheat unless you have a warning light/gauge to tell you to turn them on!!

Alternatively, you could instead run the relay coil ground (#4) through the toggle switch without any fuse protection (since your #3 wire would already have a fuse). Then, if this wire ever shorts to ground, it only turns the fans to On. But either way, if you use a toggle switch, you have to remember to turn the fans on.
 
I am installing dual fans one push one pull.
This is a no brand ebay special to get me by for now. My question is the kit comes with the relay, fans, temp sensor, and a circuit breaker specs below.
My question is I want to eliminate the temp sensor but instead have it kick the fans on as soon as the key is on. I unfortunately have seized plugs on my intake manifold so I just want to go around that.

Wiring
60 Amp Relay
30 Amp Circuit Breaker
30 Amp Inline fuse

The relay has 4 wires
Red with 30 amp inline fuse
Black - Ground
Blue - Fan trigger
White - Temp sensor

Fans - Each
Maximum Fan FAN CFM=2000 CFM
Maximum Fan RPM=2250 RPM
Number of Blades: 10 blades
Thickness=2.5″
12 Volts
6.6 AMP DRAW

So my brain is seeing it connected as battery to 30 amp circuit breaker, Red with inline fuse to circuit breaker
Black to ground source
Blue to fan
White to a ignition switch source? This is what I am looking to figure out if anyone has set up the same please let me know what you used to "trigger" the relay

Definitely not trying to hijack this thread, but was hoping you could school me...

Why one fan push & one fan pull?

Thanks
 
I don't know what your wiring package looks like but consider that a relay normally has 4 parts:
1) Input power - this is the power that it receives and is available to send to a controlled device
2) Output power - this is the power going out from the relay to the actual device being controlled
3) Signal/relay coil Input - this is a 12v wire coming in that will power the coil to close the power contacts
4) Signal/relay coil ground - this is the ground for the coil that is used to close the contacts
In your case, you need to supply the relay with input power (#1) above. Due to the inrush current of electric fans, I would think that you run a wire from your Ign source to the circuit breaker and then to the relay power input. The power output wire (#2) is then sent to the fans to power them up. This output wire is actually protected by the circuit breaker so I don't see a need for an additional fuse. But if you want, you could put the 30A fuse in this output wire.
For the relay coil, run a wire from an Ign source through a smaller fuse (maybe a 10A) to the relay "Signal" input (#3). This wire will really only run less than 0.5A so an 18Ga wire is appropriate. The ground for the relay coil is actually supposed to be the coolant sensor which will ground once the setpoint temp is reached. But since you want to run the fans straight on when the Ign is on, just run this wire to a good ground (#4).
Turning the fans on with Ign means they will run on high anytime the key is On including when the engine is cold or even cranking the car. Not sure you really want that but up to you. I'd suggest running the relay coil power (signal input #3) through a toggle switch so you can flip them on once the engine is warm or after started anyway. But you can't forget or you risk an overheat unless you have a warning light/gauge to tell you to turn them on!!

Alternatively, you could instead run the relay coil ground (#4) through the toggle switch without any fuse protection (since your #3 wire would already have a fuse). Then, if this wire ever shorts to ground, it only turns the fans to On. But either way, if you use a toggle switch, you have to remember to turn the fans on.

Yeah no toggle switch at all. I have had bad luck in the past with them and fans. As little as this car is driven or distance driven I would rather them be on all the time. I will send a pic in a minute but my 30 amp fuse is pre-wired to my hot wire on the harness so it has to be used. I guess I am confused on where the circuit breaker is supposed to come in.
 
Definitely not trying to hijack this thread, but was hoping you could school me...

Why one fan push & one fan pull?

Thanks
One to force air on to the rad when slow moving and one to pull air through to keep cool. I am running a larger rad so the more airflow I can get the better
 
Yeah no toggle switch at all. I have had bad luck in the past with them and fans. As little as this car is driven or distance driven I would rather them be on all the time. I will send a pic in a minute but my 30 amp fuse is pre-wired to my hot wire on the harness so it has to be used. I guess I am confused on where the circuit breaker is supposed to come in.
Ok Blue wire is the fan power, Black is ground, Red is battery source with the inline fuse, white is ?

image0.jpeg


image1.jpeg
 
So I did a mock setup and wired it as followed:
1. Red 3. Blue
2. Black 4. White

Fan has 2 wires one blue and one black.
I wired the #3 from the relay to the blue on the fan.
Grounded the black on the fans and #2 relay to - on battery (just to test)
ran the battery positive to the 30 amp circuit breaker
#1 with inline fuse to the circuit breaker
#4 triggered by touching to the + post on battery.
I can hear the relay click and the fans come on. My only question at this point is where is a good spot to connect the white wire that it will not get to much power in the line and melt it. I can add a fuse inline here as well. Just more looking for what to use for the trigger source.
 
White must be coil+ (86) and black coil- (85). Look at the numbers on your relay. The coil draws very little current (~30 mA), so shouldn't matter where you tap +12V, but you want either IGN or ACC which isn't powered when the car is off. BATT+ would run down the battery. I don't think A's have ACC under-hood (horn relay is always hot), so IGN is your only choice. Tap that on the upstream side of the ballast resistor (if you have one). Simple since 57 teminals and you can buy piggy-back terminals. I don't understand their temp sensor. It must be an on-off switch which turns on when hot and you must power one side w/ 12 V.
 
White must be coil+ (86) and black coil- (85). Look at the numbers on your relay. The coil draws very little current (~30 mA), so shouldn't matter where you tap +12V, but you want either IGN or ACC which isn't powered when the car is off. BATT+ would run down the battery. I don't think A's have ACC under-hood (horn relay is always hot), so IGN is your only choice. Tap that on the upstream side of the ballast resistor (if you have one). Simple since 57 teminals and you can buy piggy-back terminals. I don't understand their temp sensor. It must be an on-off switch which turns on when hot and you must power one side w/ 12 V.
All good, I tapped into my electric choke feed and that has been working so far.

The temp switch is in fact that, once at a predetermined temp the internal switch is triggered (ground circuit).
 
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