Isolated ground terminal blocks.

B

Bobert

Member
Location
Virginia
Occupation
Master Electrician
Ive recently landed on a job at a healthcare facility. We're installing new isolation panels. Out of the panels we set junction boxes with terminals so we can access it all without opening the panel. My question is about the type of terminal blocks I should be using for isolated grounds.

I have 2 grounds going out. The EGC and the isolated ground. When choosing the terminal blocks, I know the isolated ground should be feed through without bonding anything else.

For the EGC, should I be using grounding type terminal blocks so theyre all bonded to the din rail? I know the metal all needs to be bonded.

My plan is to use feed through ground terminal blocks and pull a completely separate EGC to 1 grounding terminal to bond the din rail. That way the EGC is also isolated but I still bond the din rail.
 
All of the metal parts should be bonded to the EGC. The IG should only connect to the device at the end and can be spliced with standard wirenuts if applicable. IG's are so 1990's what are these IG's actually feeding?
 
infinity said:
All of the metal parts should be bonded to the EGC. The IG should only connect to the device at the end and can be spliced with standard wirenuts if applicable. IG's are so 1990's what are these IG's actually feeding?
Click to expand...
Thanks Rob for your reply. Its a renovation of operating rooms. There are 4 new iso laser panels. They feed (2) 208v 50a laser receptacle in each OR. Theyre interesting. They have a plc in the panel and control circuits. They are de-energized while not in use. The controls go to the cover of the receptacle. When the cover opens, they become energized.
 
Are you actually feeding these units with Isolated Power Systems? Isolation Power System grounding is actually isolated by it's very nature. The grounding in these areas are for equipotential not fault clearing.
 
Might want to review also NFPA-99 6.3 as the guidance there exceeds what is covered in the NFPA-70
There are some vary nuanced details related to the "isolated ground" requirements. Also considered in '99' is the requirements referenced by roger.
 
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