Motor Control Circuit Voltage

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I would find nothing unusual about a 480V coil on a motor starter. If everything is in good order then there shouldn't be a danger. If there is a fault on the control circuit the fuse or breaker should blow, just like it should if there were a fault on the circuit for the motor itself.

Please understand the coil failed and began smoking, but there the power fuses did not blow.
 
Based on some of the responses, I wanted to provide a more thorough description of the circuit. The circuit operates a chilled water pump motor with a Size 2 starter. The circuit originates in a MCC, it is tapped off the 480 VAC power feed, the control circuit then leaves the MCC to a rheostat, then to a pushbutton station to start and stop the pump. There are no fuses for the 480 VAC control circuit voltage, so the only protection is the power conductor fuses for the motor. The motor coil failed and began smoking and did not blow the power fuses. The MCC was de-energized to stop any further damage. The motor starter will have to be replaced, so the addition of a control transformer to lower the control voltage would not be that more work. In addition, we as a facility were not aware that the control circuit was 480 VAC. At this facility we require an arc flash analysis to be performed for all 480 VAC applications, otherwise we are not allowed to operate the equipment. I would appreciate any additional comments on this based on the additional information. If there is any other questions please let me know. Thanks.

Another fact I failed to mention is that this facility's 480 VAC power system I a B-phase corner grounded system. I don't think this makes much of a difference but wanted to make sure I presented all the facts. Also, we use the ETAP software to perform our arc flash analysis, we do not use the Tables from NFPA 70E.
 
Motor Control Circuit Voltag

Motor Control Circuit Voltag

I do not see any safety improvement gained by changing things.

The reason I stated safety considerations, is that by reducing the control voltage to 120 VAC from 480 VAC you eliminate the potential for an arc flash incident at the equipment downstream of the MCC bucket. In addition, this would allow the E&I mechanics to work on 120 VAC vs 480 VAC on the same equipment if energized troubleshooting was required. One thing I am curious is no one has responded to the potential for an arc flash incident to occur.
 
...One thing I am curious is no one has responded to the potential for an arc flash incident to occur.
The impedance of the control circuit conductors acts to limit the fault current. Once you add 25-50' of #12 or #14 to the circuit, you will have a very limited arc flash hazard.
 
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