akitagandy
Member
GM 10ga to the battery , #2 jumper to the BAT,and #1 can i hook it to my cooling fan it is wired to come on with the key? The only diagram i find says hook it to a idiot light. Info will help
alt wiring ? again
- Thread starter akitagandy
- Start date
You need a relay to handle the surge of power to the fan.Also i would highly recomend an intake sending unit to come on at a certain temp.Mine is 180 thats a good number to start with.
bigfrank330
Member
Don't hook #2 to your fan
You Must hook it to your Gauge OR Idiot lite for best results
Hooking to your fan COULD do alot of damage if you have a voltage surge from the fan
Frank
You Must hook it to your Gauge OR Idiot lite for best results
Hooking to your fan COULD do alot of damage if you have a voltage surge from the fan
Frank
Wild Mango
Member
The idiot light circuit also supplies 12V to enable the regulator in the alternator to initially excite the rotor, once the rotor is energised the system becomes self exciting, the idiot lite terminal becomes +12Vdc (instead of 0Vdc) and the lite goes out. If you put Roosters 10ohm resistor in paralell with the idiot lite then the alternator will still get its initial excitation even if the idiot lite is blown.
The other small terminal (if there is one)is for the regulator to sense required output voltage, and in an ideal world you would wire it to a headlamp terminal. That way the regulator will adjust its output to give 13.8V at the headlamps, never mind the volt drop in the wiring.This is important with Halogen lamps, which lose light output quite markedly with volt drop - they need the full 13.8 for rated output. (but no more - they are intolerant of over voltage as well)
Screaming Metal
Active Member
This might also help, courtsey of the Folks at the National T-Bucket Alliance....
Electric Radiator Fan
This is a reasonably simple setup. But if it's not done properly you will experience some real headaches. So to start off properly, you will need: Heavy Gauge Wire(at least #12 or better), you will also need a Heavy Duty Relay (at least 30 amp or better), and you will need some sort of actuator switch. An actuator switch can be a simple toggle switch, it can be a temperature switch, or you can connect to the accessories terminal on you ignition. The wire to actuate the relay can be be light weight (#14 or #16) will be OK.
There are two modes an electric fan operates in.
1) PUSHER Mode. This is where the fan is placed on the front
of the radiator and "pushing" the air through the radiator.
2) TRACTOR Mode. The fan will be on the back side of the
radiator, "PULLING" the air through the radiator.
Of the two choices, the Tractor Mode is prefered. It looks better,
and works a little better.
So let's get is thing hung and operating. First, mount the fan on the back of the radiator using the pull-through straps (that came with the fan). This will be in "Tractor Mode" so you will need to test the polarity of the fan to make sure the fan is "PULLING" air through the radiator. Because this is a DC motor it can run either direction, depending on how you wire it. So test it to determine which wire will be your "hot" wire EI: going to the + of the battery. Once you have determined which one is hot, the other wire will be grounded to the chasis or motor. Now let's start wiring the "HOT" wire. Connect the "HOT" wire from the fan (using heavy gauge wire) to one of the big terminals on the relay. (NOTE: there are three terminals on the relay, two big ones, and one small one.) Using heavy gauge wire, connect the other big terminal to a main power source. The best choice here is the "BATTERY" terminal on your alternator. This will keep you new fan wire reasonably short. (Be careful here, you are working with a live wire!) You should have the heavy gauge wiring complete now. And, the fan should NOT be running! Now, the relay must be grounded. so bolt the relay either to the chasis or motor. (The fan should NOT operate!) Now for the last wire... Connect a long light weight wire to the last terminal on the relay. This is the relay actuator terminal. Now when this wire is connected to a "hot" terminal of any type, it will pull in the relay and kick on the fan. You can test it by touching this wire to the "hot" side of the relay. The fan will turn on. If every thing is working as predicted, you may connect this actuator wire to any switch you desire. It may be your ignition switch, a toggle switch, or a thermal switch. Now, just so you will know, a thermal switch is a GROUND type switch! So you will have to re-wire the relay to turn the ground on and off. So let's pass on this for now. I would suggest either the ignition or a toggle. The ignition switch will activate the fan whenever the Ignition is on. The toggle will only activate the fan when you decide you need the fan on. So I'd suggest the toggle switch.
Now for some "understanding" of why you are using a relay. A DC fan motor while starting up, will pull 35 to 50 amps. then drop to about 18 AMPS continously. This is too much load for a toggle switch of ANY TYPE! Even a 30 AMP toggle. Why? Because the toggle can't handle the surge when the fan is powering up. (35 to 50 AMPS). Eventually the toggle will burn up. Still confused? OK, toggle switches are rated by "PEAK LOAD" meaning thats all they can handle while a device is powering up. IE: a 30 AMP toggle switch can handle a peak of 30 AMPS, an a continous load of 1/2 the peak load... meaning that a 30 AMP toggle can only 15 AMPS continously! Your fan pulls 18 AMPS continously. So a toggle switch will burn up sooner or later.
Now a relay is rated differently! It is rated by continous load, meaning that it can handle half again the continous load for the peak load. So, a 30 AMP relay can handle 45 AMPS peak and 30 AMPS continously. Because the peak load o of the relay is a little lower than the fan start up load, it too will eventually burn out. But it will take a long time, depending on how often the fan kicks on and off. When the fan is running, the relay can easily handle the 18 AMPS required. So the only thing that will wear out the relay will be kicking is on and off frequently!
Now a relay is rated differently! It is rated by continous load, meaning that it can handle half again the continous load for the peak load. So, a 30 AMP relay can handle 45 AMPS peak and 30 AMPS continously. Because the peak load of the relay is a little lower than the fan start up load, it too will eventually burn out. But it will take a long time, depending on how often the fan kicks on and off. When the fan is running, the relay can easily handle the 18 AMPS required. So the only thing that will wear out the relay will be kicking is on and off frequently!
Now that I have you really confused... let me throw another wrench in your
fan...(pun intended). Not all relays are suitable for this job! There are
"CONTINOUS" Duty Cycle relays
and
"INTERMITTANT" Duty Cycle relays
Never, never use an Intermittant relay for a fan motor!! You will burn it up in a New York minute. So what is a Intermittant relay? Any relay which is used in short cycles, like a horn relay. Or a starter solenoid (starter relay). These are INTERMITTANT. An old style generator relay, or an early alternator relay is a CONTINOUS relay. Some vehicles Virtually all Industrial 12VDC relays are CONTINOUS.
And this is what you must have for your fan!
A minimum 30 AMP CONTINOUS DUTY CYCLE Relay!
-----------------------------------------------------------------
Now for the temperature switch. You don't need a relay!
Temp. switches are designed to operate fans!(assuming you are using a fan temp. switch) All you do is connect the wire from the Temperature switch to the ground on the fan motor. The hot wire on the fan motor connects directly to a battery positive source. IE: the Battery terminal on your Alternator, or go directly to the positive post on the Battery. The down side to this switch is that the fan will continue to run after the vehicle is cut-off. Then when the engine cools off the fan will stop. This pulls your battery down a little! But usually isn't a problem, unless your battery is a piece of trash and needs to be replaced.
© Copywrite 2002 National T-Bucket Alliance
All rights reserved.
Electric Radiator Fan
This is a reasonably simple setup. But if it's not done properly you will experience some real headaches. So to start off properly, you will need: Heavy Gauge Wire(at least #12 or better), you will also need a Heavy Duty Relay (at least 30 amp or better), and you will need some sort of actuator switch. An actuator switch can be a simple toggle switch, it can be a temperature switch, or you can connect to the accessories terminal on you ignition. The wire to actuate the relay can be be light weight (#14 or #16) will be OK.
There are two modes an electric fan operates in.
1) PUSHER Mode. This is where the fan is placed on the front
of the radiator and "pushing" the air through the radiator.
2) TRACTOR Mode. The fan will be on the back side of the
radiator, "PULLING" the air through the radiator.
Of the two choices, the Tractor Mode is prefered. It looks better,
and works a little better.
So let's get is thing hung and operating. First, mount the fan on the back of the radiator using the pull-through straps (that came with the fan). This will be in "Tractor Mode" so you will need to test the polarity of the fan to make sure the fan is "PULLING" air through the radiator. Because this is a DC motor it can run either direction, depending on how you wire it. So test it to determine which wire will be your "hot" wire EI: going to the + of the battery. Once you have determined which one is hot, the other wire will be grounded to the chasis or motor. Now let's start wiring the "HOT" wire. Connect the "HOT" wire from the fan (using heavy gauge wire) to one of the big terminals on the relay. (NOTE: there are three terminals on the relay, two big ones, and one small one.) Using heavy gauge wire, connect the other big terminal to a main power source. The best choice here is the "BATTERY" terminal on your alternator. This will keep you new fan wire reasonably short. (Be careful here, you are working with a live wire!) You should have the heavy gauge wiring complete now. And, the fan should NOT be running! Now, the relay must be grounded. so bolt the relay either to the chasis or motor. (The fan should NOT operate!) Now for the last wire... Connect a long light weight wire to the last terminal on the relay. This is the relay actuator terminal. Now when this wire is connected to a "hot" terminal of any type, it will pull in the relay and kick on the fan. You can test it by touching this wire to the "hot" side of the relay. The fan will turn on. If every thing is working as predicted, you may connect this actuator wire to any switch you desire. It may be your ignition switch, a toggle switch, or a thermal switch. Now, just so you will know, a thermal switch is a GROUND type switch! So you will have to re-wire the relay to turn the ground on and off. So let's pass on this for now. I would suggest either the ignition or a toggle. The ignition switch will activate the fan whenever the Ignition is on. The toggle will only activate the fan when you decide you need the fan on. So I'd suggest the toggle switch.
Now for some "understanding" of why you are using a relay. A DC fan motor while starting up, will pull 35 to 50 amps. then drop to about 18 AMPS continously. This is too much load for a toggle switch of ANY TYPE! Even a 30 AMP toggle. Why? Because the toggle can't handle the surge when the fan is powering up. (35 to 50 AMPS). Eventually the toggle will burn up. Still confused? OK, toggle switches are rated by "PEAK LOAD" meaning thats all they can handle while a device is powering up. IE: a 30 AMP toggle switch can handle a peak of 30 AMPS, an a continous load of 1/2 the peak load... meaning that a 30 AMP toggle can only 15 AMPS continously! Your fan pulls 18 AMPS continously. So a toggle switch will burn up sooner or later.
Now a relay is rated differently! It is rated by continous load, meaning that it can handle half again the continous load for the peak load. So, a 30 AMP relay can handle 45 AMPS peak and 30 AMPS continously. Because the peak load o of the relay is a little lower than the fan start up load, it too will eventually burn out. But it will take a long time, depending on how often the fan kicks on and off. When the fan is running, the relay can easily handle the 18 AMPS required. So the only thing that will wear out the relay will be kicking is on and off frequently!
Now a relay is rated differently! It is rated by continous load, meaning that it can handle half again the continous load for the peak load. So, a 30 AMP relay can handle 45 AMPS peak and 30 AMPS continously. Because the peak load of the relay is a little lower than the fan start up load, it too will eventually burn out. But it will take a long time, depending on how often the fan kicks on and off. When the fan is running, the relay can easily handle the 18 AMPS required. So the only thing that will wear out the relay will be kicking is on and off frequently!
Now that I have you really confused... let me throw another wrench in your
fan...(pun intended). Not all relays are suitable for this job! There are
"CONTINOUS" Duty Cycle relays
and
"INTERMITTANT" Duty Cycle relays
Never, never use an Intermittant relay for a fan motor!! You will burn it up in a New York minute. So what is a Intermittant relay? Any relay which is used in short cycles, like a horn relay. Or a starter solenoid (starter relay). These are INTERMITTANT. An old style generator relay, or an early alternator relay is a CONTINOUS relay. Some vehicles Virtually all Industrial 12VDC relays are CONTINOUS.
And this is what you must have for your fan!
A minimum 30 AMP CONTINOUS DUTY CYCLE Relay!
-----------------------------------------------------------------
Now for the temperature switch. You don't need a relay!
Temp. switches are designed to operate fans!(assuming you are using a fan temp. switch) All you do is connect the wire from the Temperature switch to the ground on the fan motor. The hot wire on the fan motor connects directly to a battery positive source. IE: the Battery terminal on your Alternator, or go directly to the positive post on the Battery. The down side to this switch is that the fan will continue to run after the vehicle is cut-off. Then when the engine cools off the fan will stop. This pulls your battery down a little! But usually isn't a problem, unless your battery is a piece of trash and needs to be replaced.
© Copywrite 2002 National T-Bucket Alliance
All rights reserved.
rooster57
Member
YOU can solve this problem by just simply getting yourself a one wire alternator!!!!!!!!!!!!!!!
Also when you install your electric fan drop me a note and i will draw you a super simple diagram to run it directly off your alternator no crazy switches to flip no temp ranges to set SUPER SIMPLE I PROMISE
Also when you install your electric fan drop me a note and i will draw you a super simple diagram to run it directly off your alternator no crazy switches to flip no temp ranges to set SUPER SIMPLE I PROMISE
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