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using 220VAC for motor local control panel

using 220VAC for motor local control panel

using 220VAC for motor local control panel

(OP)
we specified the use of 220VAC for motors loacal control panel which will contain mainly start/stop push bottoms.
some of the motors will be 225 meter away from MCC, we are using 2.5mm2 cable(#14 AWG)three conductor cable for that.
my question is: due to the long distance is it possible that the cable will act as a capacitor and then we will be unable to stop the motor because of the capacitive effect of the cable which will keep the contactor coil energized?
and if we use 110VDC is this will be better?
  

RE: using 220VAC for motor local control panel

Yes, it's possible, if you have control devices locally at the motor.  It's the distance of the control circuit, not the power circuit that is the issue.  The distributed shunt capacitance of the control circuit reaches a point where it can maintain the coil voltage above the dropout voltage even when the remote contact is opened.  

I have a very old data sheet showing that for a #12 AWG three-wire control circuit in wet conditions at 240V (60Hz), the maximum control distance is 115 feet.  For two-wire control it gives a maximum of 230 feet.  

I'm guessing your system is 50 Hz, so distances will be somewhat greater.  

This would not be a problem with any dc control power voltage.  

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