Capacitive current contribution - calculation
Capacitive current contribution - calculation
(OP)
Hello,
Can you share your thoughts on calculation of capacitive current calculation in a industrial electrical system.
I see a recommendation in one of our reference documents says like this
"capacitive contribution to the earth fault on the part of the 11 kV cables shall be less than the resistive ground current in order to avoid hazardous overvoltage"
This is when we have HRG limiting the alternator e/f current to ~5 amps.
Can ETAP do this calculation anywhere?
Thanks for your responses in advance
Can you share your thoughts on calculation of capacitive current calculation in a industrial electrical system.
I see a recommendation in one of our reference documents says like this
"capacitive contribution to the earth fault on the part of the 11 kV cables shall be less than the resistive ground current in order to avoid hazardous overvoltage"
This is when we have HRG limiting the alternator e/f current to ~5 amps.
Can ETAP do this calculation anywhere?
Thanks for your responses in advance






RE: Capacitive current contribution - calculation
Cable capacitance may be modeled in ETAP - depends on their cable model. I doubt that they actually calculate the leakage current on an ungrounded system, but you could get the cable data for your hand calculation.
Any result over about 10 amps is highly suspect.
RE: Capacitive current contribution - calculation
RE: Capacitive current contribution - calculation
CODE --> dpc
Am I wrong in thinking that transformers/generators contribute negligible capacitance? I would have thought the largest contributor would be power factor correction banks followed by cables, unless there's some other unusual loads on the network.
PF banks will have their capacitance specified and cables can be calculated from cable data, as long as you have lengths and types. Are there other sources I'm missing?
RE: Capacitive current contribution - calculation
RE: Capacitive current contribution - calculation