How to Calculate/formula Current Leakage (mA) in Distribution system

[jonos]

Dear everybody,
Do you know how to calculate current leakage in distributin system?
Usually if I want to know the current leakage, I use the Clampmeter.
Thank you for your attention.
Regards
jonos

 

[Electrifier]

Put the clamp meter on cable(with out ground conductor and armoured)you will find the leakage current, but the clamp meter suppose to be very fine. The leakage is almost equal to the phase voltage divided by insulation resistance of distribution circuit for single phase.

 

[jonos]

Dear Electrifier,
if single phase, which cable do we measure for insulation resistance? phase cable or ground cable, after that voltage divide total insulation resistance or one of them?
I'm sorry my english was not good.
Thank you.

 

[redtrumpet]

jonos - Mining Cable Engineering Handbook by Cablec has formulas for calculating cable capacitance, insulation resistance, and charging current. I got my copy from my local electrical distributor. Federal Pioneer in Canada (now part of Schneider Electric) used to publish a book on high-resistance grounding which contained useful charging current data. I got my copy from my local Schneider rep. In other words, this information is available in several forms if you put some initiative into looking for it.

In the absence of any other calculation, you can estimate 1 A of charging current per 2000 kVA on an LV system and 1 A of charging current per 1000 kVA on an MV system.

 

[Electrifier]

Jonos. Switch off the main breaker and switch on all distribution breakers and switches. Measure the insualteion resistance with Megger with any cable (Phase or neutral)