xfmr ground

[pookcat]

Installing a new 45kva transformer on the 4th floor of a hospital and there is no building steel or water pipe near. Can the sprinkler pipe be used?

 

[jumper]

I would say no. It is not listed in 250.30(A)(4) or its exceptions that list alternatives in 250.52.

 

[augie47]

Many sprinkler systems use a type coupling that actually isolates sections of the piping so they are useless as a ground plus Sprinkler Codes in many areas prohibit using them as a ground

 

[jumper]

Many sprinkler systems use a type coupling that actually isolates sections of the piping so they are useless as a ground plus Sprinkler Codes in many areas prohibit using them as a ground

I gave NFPA 13 a quick search, but I could find a prohibition, I think it is there somewhere: I just did not find it.:ashamed1:

I am most familiar with sprinkler head placement and hanger rules.

 

[jumper]

Found it!!! NFPA 13, 10.6.8

 

[brian john]

I would assume there are other transformers feeding loads on the 4th floor. What did they utilize for the GEC.

 

[Smart $]

Installing a new 45kva transformer on the 4th floor of a hospital and there is no building steel or water pipe near. ...

Run the GEC with the feeder...???

 

[dkidd]

Many sprinkler systems use a type coupling that actually isolates sections of the piping so they are useless as a ground

Victaulic fittings are actually UL listed for bonding, so I don't know what fittings you are refering to.

As for water pipe, it is only permitted as a ground electrode if the grounding electrode conductor is connected within 5 feet of where the pipe enters the building