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Max voltage /heat problem

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No, but I'm out of town right now. I had everything (resistor, cap) in line with the coil. I actually ended up cutting the delay module from a timing relay and attaching it to my board, just for the sake of getting a working prototype of the whole thing. I will be going back and trying to use the delay you showed me on a later prototype. For now I just need to prove the concept.
 
No, but I'm out of town right now. I had everything (resistor, cap) in line with the coil.
That would be the source of your problem then. The snubber network needs to be in parallel with the coil as shown in my diagram, not in series like I think you are describing.
 
O.K. to revive this thread from the dead. I got back to this project and breadboarded the delay that KCristie put up (the second one with the two transistors). It works, but as diagramed it only gave me a about 17 seconds of delay (about 1/3rd of what I need) so I changed the 82K resistor for another 220K and bingo 47 sec +/-.... it's perfect, except one of the transistors is pretty hot (90 to 100 F).
 

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I've been checking the parts and the transistors are 2222a where the diagram calls for 2222 any idea if this could be all or part of the problem?
 
so I changed the 82K resistor for another 220K and bingo 47 sec +/-.... it's perfect, except one of the transistors is pretty hot (90 to 100 F).
Instead of changing the 82K resistor, you need to replace the 1000uF cap with a 3300uF one. The 82K/220K divider, while it sets the timing, also sets the voltage drop across the transistors. You won't have 24V available for the relay when the timing cycle is over if you change the divider ratio the way you did. You could add a heatsink to the 2nd transistor or swap it for one in a TO-220 case.
 
Is there a combination of resistors that would give me the correct time delay, have acceptable voltage drop and not require a bigger cap? I'm near the size/space limit for my project with the 1000 cap.
 
You could try a 270K and 750K combo to replace the 82K and 220K resistors. At these values the beta of the transistors and the relay load come into play, so you may have to experiment a little. Just make sure that the relay coil voltage doesn't rise above apx 28V or remain below 19V during normal operation.
 
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