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Author Topic: Diode in SERIES with Relay Coil  (Read 491 times)
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What would be a good diode to prevent a NO relay from closing when reverse polarity is applied to a circuit via a drunk wiring said circuit by placing a diode in series with the coil, assuming relay current is less than 300mA?

Note: This is NOT for back EMF protection, just trying to prevent frying a SABERTOOTH if  wired up backwards and flip on the switch which controls a relay
« Last Edit: June 22, 2013, 10:03:06 am by mech_eng » Logged

Manchester (England England)
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Use a series diode rather than a parallel one. To minimise voltage drop use a Shockley diode.
http://en.wikipedia.org/wiki/Shockley_diode
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Use a series diode rather than a parallel one. To minimise voltage drop use a Shockley diode.
http://en.wikipedia.org/wiki/Shockley_diode
Did you really mean a Shockley diode or did you mean a Schottky diode?
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Use a series diode rather than a parallel one. To minimise voltage drop use a Shockley diode.
http://en.wikipedia.org/wiki/Shockley_diode
Did you really mean a Shockley diode or did you mean a Schottky diode?

OK
http://en.wikipedia.org/wiki/Schottky_diode
I am dyslexic.
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I haven't got my head around the circuit that this would be protecting, but if you want to arrange that a solenoid can be operated by a forward voltage but not a reverse voltage then a series diode seems to me to be a sensible way to do it.
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Use a series diode rather than a parallel one. To minimise voltage drop use a Shockley diode.
http://en.wikipedia.org/wiki/Shockley_diode
Did you really mean a Shockley diode or did you mean a Schottky diode?

OK
http://en.wikipedia.org/wiki/Schottky_diode
I am dyslexic.

So is my son, so you have my sympathy.
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