Earthing of equipment

[NM13]

In electrical maintenance field there is a practise to measure Earth resistance of earth pit on periodic interval.

Is there any method to check/confirm the continuity of the earth conductor between earth pit (grid) to the equipments

Generally population of the electrical equipments are too large in industry,in that case what will be the pratical method.

 

[7anoter4]

The high-current method of testing ground grid continuity and connections is a reliable, accurate method
of detecting faults in the ground system. Some one do it by means of parallel connected welding transformer in order to achieve 300-1000 A and a measuring accuracy.
See-as example:

http://www.hccontrol.co.za/Search/Suppliers/Megger/grndResTestEquip/Datasheet/GTS300_DS_en_V10.pdf

or see:

http://www.mittoninstruments.com/docs/Practical Testing of Grounding Systems.pdf

 

[NM13]

Dear 7anoter4,

Thanks for guidance but as you well aware the earthing grid acroos the plant (industry)passing thr several steel structure and if we adopt current injection method, practically it's not possible.
If any other way to test it, let us know.
Thanks

 

[7anoter4]

There are a lot of "Clamp-On Ground Resistance and Leakage Current Tester" on the Web- see for instance:

http://www.mecoinst.com/newproducts/newproduct_details.asp?product_id=49

or this one:

http://www.farwst.com/fwst/instrum/erico05.htm

It is very easy to use, at least according to the web information.
I never used this and I could not recommend it.

 

[dpc]

Check clamp-on resistance meter at AEMC website. They have some technical info on the principles and suitability of this method.