# Resistor for Under Voltage Release



## just the cowboy (Sep 4, 2013)

Is it a wire wound with a tap?
It is probably the drop out setting, voltage drop across adjustment triggers drop out.

Watch work on elevators for liability reasons, since it has something it usually needs to go back that way.

Cowboy


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## samgregger (Jan 23, 2013)

How big of a breaker and what type?


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## emtnut (Mar 1, 2015)

cbeckmeyer said:


> My question is, what exactly is the purpose of that resistor?


It sets the current to hold the coil in the breaker.
120V - no resistor
240V - 480 etc, have the external resistor.

You mentioned disconnecting it to try, that will keep the breaker off.
If you can't find a replacement, time for a new panel or sub


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## cbeckmeyer (Jun 4, 2018)

samgregger said:


> How big of a breaker and what type?


Its a 90 amp Westinghouse Breaker AB DE-ION


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## cbeckmeyer (Jun 4, 2018)

emtnut said:


> It sets the current to hold the coil in the breaker.
> 120V - no resistor
> 240V - 480 etc, have the external resistor.
> 
> ...


I know that disconnecting it will keep the breaker off. I was hoping to pull the UVR out of the breaker completely.


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## samgregger (Jan 23, 2013)

cbeckmeyer said:


> I know that disconnecting it will keep the breaker off. I was hoping to pull the UVR out of the breaker completely.


 I think you would have to open and therefore modify the breaker to do that, and you probably don't want the liability of doing that. 
I agree that hanging a sub panel off the side of the main with a new breaker or fuses is going to be best, but coordinate with the elevator guys on exact what characteristics it needs.


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## cbeckmeyer (Jun 4, 2018)

just the cowboy said:


> Is it a wire wound with a tap?
> It is probably the drop out setting, voltage drop across adjustment triggers drop out.
> 
> Watch work on elevators for liability reasons, since it has something it usually needs to go back that way.
> ...


This is a grainy photo. Sorry, I don't know much about resistors. Top one is for 1 breaker, bottom one is for another.


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## cbeckmeyer (Jun 4, 2018)

samgregger said:


> I think you would have to open and therefore modify the breaker to do that, and you probably don't want the liability of doing that.
> I agree that hanging a sub panel off the side of the main with a new breaker or fuses is going to be best, but coordinate with the elevator guys on exact what characteristics it needs.


Gotcha, yeah I know that with some breakers you can add UVR or Shunt trip relays into them if needed. The elevators were upgraded from original at some point. Downstream of this breaker is a new ECB with a shunt trip (for the heat detector). I figured they probably don't even need the UVR in that breaker being as the elevators probably have some sort of under voltage monitoring, but i should probably reach out to them to verify before id do that. Really, i think i will just recommend upgrading the panel entirely. Its only a matter of time before the same thing happens to another breaker in the panel. Thanks


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## just the cowboy (Sep 4, 2013)

@cbeckmeyer This is a wire wound resistor. They are meant to be a power load. As @emtnut said if they are using it in series with the trip coil they may use a fixed one for a set voltage drop or they may use one like the one pictured so it could be used for different voltages. If it has a wire connected to the middle connection on the one you have you can try moving it a small amount ( one or two wires ) towards the end that has a wire connected to it.

Think of it as a pot.

Good luck tell us how you fixed it
Cowboy


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## micromind (Aug 11, 2007)

I don't know the elevator code but there's no way I'd use an under voltage trip on a breaker that feeds an elevator. A power failure is very likely to result in people getting stuck in the car.


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## MadSparky (Mar 2, 2018)

Definitely call an elevator contractor. Specific license in my state.


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