Looking for a relay, Anyone got recommendations

[AM.MSCL]

I am needing to find a relay to take two different inputs and send a single output to the input on for another relay. This is for the electric fan I have in my 69 Firebird.
I talked to Painless wiring but the guy gave me the part number to a single input/single throw which I don't think is correct.

Input 1 is the Fan Switch Temp in motors water passage (max 1 amp 12 volt)
Input 2 A/C Clutch Engagement Switch turn on (max 1 amp 12 volt)
Output 1 amp 12 volt going to the input on for the fan relay
12 Volt battery
Ground
Is this something I can get at the auto parts store?
Anyone have a part number of a particular brand?
Thanks
Ray

[wiedemab]

Couldn't you use a switch to ground to ground the relay. It wouldn't matter which of the switches made the ground, the AC or the temp switch.

You may need to two relays to do it that way though....................

[AM.MSCL]

Brandon
This is what I do not know. Painless said the input wire for the existing relay I have that connects to the fan temp switch that I have in the engine block receives a low amp 12 volt signal to energize the relay circuit.

Now thinking about how the fan temp switch should work:
It finally gets to the require coolant temp it then establishes a path for the circuit to ground so the + current comes from the relay to ground in the engine block.

So if the A/C engagement circuit does the same then the current from the existing relay would not care which path if has both would be active and the electric fan would work?
This is a vintage air system with a March A/C compressor.

[AM.MSCL]

I want the electric fan on the radiator to come on when the A/C is on and/or when the temp fan switch in the motor reaches the determined temp to start cooling the motor.
In the winter the a/c on the car stays off and the engine coolant reaches say 180 degrees which is what the fan temp switch establishes path to ground to turn on the electric fan.
In the summer the a/c is on so it enables the electric fan as recommended/required by Vintage Air
Now in the summer the a/c is on and the electric fan is on; the engine finally reaches the coolant temp of 180 degrees so another signal to turn the fans on is established but not needed since the electric fan is on already. BUT I don't want to short out the existing relay that supplies power to the electric fan due to it now having 2 on signals and I also don't want the A/c and fan temp switch fighting each other or shorting each other out also.

Hopefully this is a better description of what I am looking to do.
thanks
Ray

[67rstbkt]

Are the two inputs the same? Both ground or both power? If so, maybe you can use the single relay with the two inputs by isolating them from each other with a diode.

[AM.MSCL]

talked to Vintage air and determined I needed a specific switch from them for electric fan to work with their kit and it takes care of the wiring for 2 sources at the same time.
Yeah!!!

[H2Ogbodies]

Running them the way you want is a non issue as long as you run relays with tamping diodes. You won't short anything out but imo I would use a third relay to drop out the engine temp switch relay trigger when you engage the AC. You can wire the AC relay so that when energized, it opens the ground circuit on the temp switch relay since it is ground activated anyway. So when you shut the AC off, it closes the ground contacts allowing the engine temp switch relay to "come online" as it were for fan operation. With a Vintage Air kit though, you should run a more robust fan assembly to pull heat out of the condensor.

[prostreet69camaro]

talked to Vintage air and determined I needed a specific switch from them for electric fan to work with their kit and it takes care of the wiring for 2 sources at the same time.
Yeah!!!

I believe it is called a binary switch.

[CamaroAJ]

you could make your own set up. i drew this up real quick.

[H2Ogbodies]

Thats a good diagram. The only issue is finding a SPDT relay that will handle more than 30 amps for a high powered fan setup. I use 70, 80 and 100 rated relays but they are all SPST types, I can order 40 amp SPDT relays but I haven't been able to find anything higher...plus, all HD relays usually have internal tamping diodes for current flow direction which won't work with the setup you drew up.

[CamaroAJ]

GM stater relay from the starter relay recall on J body cars and they are 40a. 85 and 86 can be switched when he wires it so they the ground goes to the sensor and ground to ground. i have used these relays on many fans with no issue.

[AM.MSCL]

Vintage Air calls the switch a Trinary Switch (spelling may be wrong).
Here is what I have:
Ford 2 speed electric fan from a 92-95 T-Bird
Painless Wiring 70 Amp Fan Relay/Fuse
Painless Wiring Fan Temp Switch (provides a path to ground) to activate the relay switch
Vintage Air Trinary Switch (provides a path to ground) to activate the relay switch also
The Fan Temp and Trinary switch are wired in Parallel so either will turn the fan on and if the other does happen to come on after the other has been on it has no effect.
I have the highest speed of the fan wired up and did not bother with the slower speed.

[AM.MSCL]

Thanks for trying to help out guys.

[esenior]

Definitely sounds like the trinary switch is the way to to. If you need more information, this link has a good visual of how the switch works and how to wire it:
http://www.hotrodders.com/forum/atta...chmentid=14367

[Swairlines]

Check PartsExpress