Thanking you for your thoughts
The 3 in a row relays are fixed / can't change em ..... only the 2 at the bottom are what I want to add to control the direction of the 12v
If i didn't have the A/C relay ... then 12v would be sent back up to the A/C itself .... Basically the relay is to isolate the A/C power source and keep the feed direction towards the fans / relays
The same for the center blue relay ....
Mike
With mechanical switches the diodes probably don't matter. With transistors you need the diode to stop the voltage spike when you stop the drive to the coil, otherwise you end up puncturing the drive transistor.
As you know the diodes will only allow power to pass one way but have little resistance in the forward polarity.
Just thinking.... If you can't come up with a relay with resistor just wire in a small globe (2 to 5w) from the earth to the switching pole and see if the problem goes away.
There you go.... If it works just another hole to drill in all that plastic for another thingy
Tony
You still have the original condensor fans yea? if so, junk the relay setup, as you don;t need the AC input, the way they achieve low speed high speed is either operating them in series/paralell, basically junk the lot, use 2 relays to control the fans with you thermatic switch and your done, makes the whole lot simple and easy to fault find, plus if one fan craps its knickers, it don;t effect the other
I've wired more than one set off falcon fans, in both retaining the original control, for falcon engine conversions and just utilising the fans for others
| Search AULRO.com ONLY! | 
    Search All the Web! | 
  
|---|
| 
 | 
 | 
Bookmarks