I believe that I am having a voltage drop issuue in a control circuit used to pull in a motor contactor. I have a control circuit that goes out a pretty long distance on a conveyor belt and then returns to an MCC to pull in the coil on a starter. After trying to run the motor I have found that the motor would run for a little bit, and the the coil on the starter would burn up/blow. When measuring the voltage across the coil (120V coil) during starting I am seeing about 110V which indicates that there is a slight voltage drop. Would this voltage drop be enough to damage the coil? I was told that with this voltage drop we would be pulling more current through the coil and that is what is causing it to blow. Is this correct?

I could understand why the voltage drop would cause more currnet to flow, but I cannot see it mathmatically. Rearranging ohm's law V=IR you would be able to calculate the current by I=V/R. But mathmatically if you decrease the voltage in the numerator of this equation with the "R" held constant it seems like your current value would be less. Is this an accurate representation of this scenario?

Thanks

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