I am trying to find a relay for a project but I have not had much luck. I'm hoping someone here can help me find it what I need. Here is what I'm trying to do:
I'm creating an airplane hanger door opener using 2 motors. I have the remote control but I need a relay that will control the 10amp 120VAC motors. The relay needs to be normally open at rest state. When I apply 12VDC to one set of contacts the relay will turn on one motor. Then when 12VDC is applied to the second set of contacts the second motor is turned on. At no time should the relay allow both motors to be on at the same time.
The remote control has 2 buttons. When button "A" is pushed it will supply 12VDC to one set of contacts on the relay to turn on one motor. When the button is released the relay should return to an open position. When button "B" is pushed the relay should go the other direction and turn on the second motor.
I have looked at normal DPDT relays but they don't seem to do what I want. Any help or suggestions that any one can give would be greatly appreciated.
Looks like you need 2 relays (dual-coil relays are latching type). Try something like this very quick sketch:
Circuit protection and contact arc suppression not shown.
When pushbutton A is pressed, relay A will turn on motor A and disconnect 120VAC power to relay B. Therefore, both motors cannot operate at the same time even if both pushbuttons are pressed.
Regards, dlloyd
dlloyd:
Looks like you need 2 relays (dual-coil relays are latching type). Try something like this very quick sketch:
Circuit protection and contact arc suppression not shown.
When pushbutton A is pressed, relay A will turn on motor A and disconnect 120VAC power to relay B. Therefore, both motors cannot operate at the same time even if both pushbuttons are pressed.
Regards, dlloyd
Thanks much dlloyd. That looks like it would work well. Sometimes you tend to place self restrictions on your thought process. In this case I kept thinking a single relay but your solution applies the KISS principle which I always like. Basic electronics training has been 35 years ago for me, I don't have much need for doing board level work these days. I have been managing data system for the last couple decades. But I have started to play around with the arduino board some for another project i have in mind. It's great that you guys have such an active forum to help kick start the old grey matter a little bit.