Grounding of Equipment

[JGnewjersey]

See attached photo

The PT transformer is grounded to the steel. The 13kv cable shield is grounded to the steel.

I believe both should be connected to the copper ground grid connection at the base of the steel. Not to the steel and then to the copper ground grid.

Please help me with references that I can use in my claim, if I am correct.

Many Thanks
JGnewjersey

 

[JBUDA54]

If the steel has a proper connection to the Grounding electrode system (see definition in Part III of Article 250(specifically2 250.52 (A) (2) of the NEC) then yes connecting to the steel is permitted.

If you have access to the NEC handbook that have nice illustrations that convey the above code references to assist you in understanding what is trying to be conveyed.

Exhibit 250.29 in the Handbook has a picture of a panel that connects to building steel which is connected to the ground ring.

A quick search returned some other discussions and info related to your inquiry.

http://ecmweb.com/content/hard-facts-about-bonding-steel

http://forums.mikeholt.com/showthread.php?t=138399

http://www.inspectionbureau.com/pdf/Grounding-Electrode-Systems-2014.pdf

So you are correct if the above code references are not met and your adversary would be correct if it does.

 

[JGnewjersey]

Thank you