Electronics

jwconklin · Joined: 03 Sep 2006 Posts: 2 Location: Ceresco Michingan

I have a simple 120VAC circuit it has two switches and one motor (1/10 HP) in series,
switch "A" is a thermostat switch "B" is a SPST used to disable motor.
What I what to do is have a LED in a remote location to indicate weather switch "B" is open or closed irregardless of what switch "A" is.

switch "A"....switch "B"....switch "B" condition
------------------------------------------------
open............open............~ ohms
open............closed..........0 ohms
closed..........closed..........0 ohms
closed..........open............120 VAC

Any ideas?

Thanks

neon · Joined: 25 Feb 2006 Posts: 594

simply stated you want to know if the motor has power. At the motor tie a 600 v 1n4007 diode anode add a 15k 1.5w in series and put a LED in series to it. this all series mess is across the motor. for remote indication run wires from the resistor to LED anode. and return the wire LED cathode to the motor. There is less then 10 ma flowing. Of course you can get fancy and do it with RF transmitter.

jwconklin · Joined: 03 Sep 2006 Posts: 2 Location: Ceresco Michingan

What I need too know is if switch "B" is open or closed, the motor my not have power if the thermostat is open.
Switch "B" is in between switch "A" and the motor.
I have about 100 feet of 22AWG or 24AWG bell wire under ground for the remote LED.

Thanks

neon · Joined: 25 Feb 2006 Posts: 594

It seems to me that no matter how many switches are there in series with the motor if you monitor the motor voltage you will know if it got power. NOW IF YOU WANT TO KNOW THE SWITCHES CONDITION THEN YOU NEED SOME DIODES GATES TO SORT IT OUT.

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