During the construction of a new heating plant it was brought up that the skid and structural steel were not earth grounded. These are 300+ hp pumps and the argument was that the case and skid should be earth grounded due to inductive charge build up. As far as I can tell, and others have verified, the grounding / bonding for the distribution is spot on to code. But checking the old heating plant, all large equipment frames, skids and structural steel are indeed grounded in addition to normal grounding/bonding.
My questions are:
1) Does the casing/frame need to be earth grounded at the motor skid?
2) If the answer to the first question is no, does the existing grounding in the old plant pose any possible problems?
3) Is this something that changed a while back? (the old plant was built in 1900 is but has been updated in 1970's and in 1992)
I know that this is a broad question with a bunch of variables, but I am hoping that there is someone out there that has seen this specific problem and could walk me through it. Thanks in advance.
My questions are:
1) Does the casing/frame need to be earth grounded at the motor skid?
2) If the answer to the first question is no, does the existing grounding in the old plant pose any possible problems?
3) Is this something that changed a while back? (the old plant was built in 1900 is but has been updated in 1970's and in 1992)
I know that this is a broad question with a bunch of variables, but I am hoping that there is someone out there that has seen this specific problem and could walk me through it. Thanks in advance.