Danger of electrocution from ungrounded system
Danger of electrocution from ungrounded system
(OP)
Just wondering what will happen if one inadverently comes in contact with one phase of 22kV feeder conductor fed via ungrounded source? I have read that such a system will sustain fault current due to phase to ground capacitances[highlight ][/highlight] of healthy phases.Could this capacitive current be fatal? Please share your views.






RE: Danger of electrocution from ungrounded system
Regards
Marmite
RE: Danger of electrocution from ungrounded system
RE: Danger of electrocution from ungrounded system
RE: Danger of electrocution from ungrounded system
RE: Danger of electrocution from ungrounded system
RE: Danger of electrocution from ungrounded system
If you touch the faulted conductor, then the current amplitude between you and ground will be based on your bodies impedance to ground relative to the faulted conductor's impedance to ground (in parallel) and unrelated to the capacitance from ground - neutral which is in series. Both current amplitudes (conductor - human - ground and conductor directly to ground) are affected by the same capacitance.
RE: Danger of electrocution from ungrounded system
For instance, for small transformer[100 kva] and short supply cable[10 ft] a 50 kg human body will be damaged in less than 1 minute.
For large transformer[1000 kVA] and medium supply cable length[1000 ft] the 50 kg body will be damaged in less than 0.1 seconds.
RE: Danger of electrocution from ungrounded system
Here where I live the 20 kV system neutral is compensated using Petersen coil, so that the earth fault current is very low: nonetheless most accidents on that lines are fatal (http://www.corriere.it/cronache/12_novembre_27/lad...)
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