High Impedance Grounded Neutral

[pete m.]

Looking at the informational note following 250.36(C).

There it states: "The impedance is normally selected to limit the ground-fault current to a value slightly greater than or equal to the capacitive charging current of the system."

Is there a way to calculate this value or is it a value that can only be determined by taking readings?

Pete

 

[jim dungar]

There a several 'rules of thumb' used to estimate charging current.
The large HRG manufacturs, like Post-Glover and I-Gard, have technical papers dealing with this topic.

 

[pete m.]

Thank you, Jim.

Pete