Grounding Issue

[mburger77]

I am in the National Guard and I am in Kandahar, Afghanistan. We are building K-spans which are steel buildings to help different types of military units complete their missions. I have a problem I am getting 7miliamps on my ground ring which is 120'X60" around the building and I have 4miliamps on the ground when the generator power is off. Is this an issue that will affect any operation of equipment? There is an inspector from Europe telling me that this is the reason for him failing the inspection. Can you give me some guidance on how to fix the issue
Thanks for your help in advance
Msgt. Palmer
Ohio National Guard

 

[dereckbc]

Failed you for 4 ma? That is pretty ridiculous as most ground systems will have some leakage current even if extremes measure are taken to prevent it.

The most common cause is multi-grounding the grounded circuit conductor (aka neutral conductor) However if that is the case it will be a lot more than 4 ma if there is real load currents flowing. Check your generator grounding. Is it SDS or not? Also check any transformers. More then likely if you have a problem it will be because something is configured wrong like a transformer that is configured as SDS feeding a distant building where the neutral is bonded to ground again at the entrance causing load current to flow on grounding conductors and earth.

Also just curious do you know if the country utility uses MGN (multi grounded neutral) transmission and/or distribution on their electrical system? If so that would certainly be a source for which there is nothing you could do about it except what you have done using ground rings to short out any potential gradient voltages.

EDIT NOTE: Thank you for serving.
God Bless You.

 

[brian john]

You could have that much error in the meter.