h Effect of cable capacitance


Effect of cable capacitance

Q)What is Effect of Cable Capacitance on the Operation of AC operated Contactors

When long length of cables is used the stored energy in the capacitance of the cable holds the contactor even after the closing command is removed. Typical value of capacitance for two core cable is 0.3 micro farad/km


Fig:Stray capacitance

Remedy:

1) Use of DC control supply voltage
2) Use of lower supply voltage
3) Short circuiting of contactor coil during off command by additional bridge contacts.
4) Use of large contactors


.......

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