Dear Mr. SYAMAL KUMAR SARBADHIKARI (Electrical)
" Can we use cu 5CX2.5 mm2 control cable for Local Push Button Station at a distance of 480 Meter from Motor Control Centre . Control Supply voltage is 110VAC."
1. Your question is on the [influence of the length of conductors used in contactor control circuit]. Under certain conditions the excessive length of the control circuit conductors may prevent the contactor from:
a) not closing: due to excessive voltage drop (in ac or dc),
b) not opening: due to excessive capacitance (in ac).
2. Influencing factors:
a) voltage, conductor size, length and the [pull-in VA of the contactor],
b) the wiring (e.g. via maintained push-button or via momentary push-button...). These may be caused by i) high control voltage, ii) low coil holding consumption, iii) low contactor dropout voltage, [the line capacitance etc....].
3. These information are published in the "contactor " catalogues of major contactor manufacturer, based on their own product.
4. Your data did not specified the [contactor(s) pull-in and holding VA].
Che Kuan Yau (Singapore)