Emergency Push Button - Distance Considerations

Desert Sparky

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Location
Desert
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Electrical Engineer
I’m curious if anyone has any input regarding the design below:

I have an EPO about 350’ from my building. This EPO ties to a contactor for emergency shut-down of a few circuits that are routed through the contactor (power source is next to the EPO). I’d like this same EPO to shut-down circuits inside of my building simultaneously with my outside circuits, so I’m specifying a second contactor, tying it to my EPO, and then routing my interior circuits through this second contactor (these circuits are from a power source inside of the building).

That said, does anyone see any code or installation issues with this configuration? The EPO is pretty far from the contactor inside of the building, so I’m curious about voltage drop, but I’m not sure exactly how much I need to upsize the my 120V EPO circuit. What kind of “load” does a signal circuit like this typically see?
 
Have you considered a small plug-in interposing relay to carry the coil voltages of your contactors? It can be located close to the contactors so that the only current on the EPO circuit is the tiny coil of the interposing relay.
 
The trick is to match the power feed through voltage to the coil voltage. EPO is connected to the LOAD side of the contactor and interrupts the coil shutting it down until you start again.
 
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