Hi,
I think he may be confusing that Grounding bushings are required on concentric/eccentric knockouts when used on a SERVICE.
I will have to dig up the article but I know a lot of inspectors who will not pass an inspection for this.
Look at 250.92 (B) last paragraphs.
I will see if I can find the reference in Stallcups Designing Electrical systems and the code...I know I saw that somewhere.
As far as the oxygen question, just consider this...how many places is oxygen bottles used? HUNDREDS IF NOT THOUSANDS. They are in bedrooms, cars, planes, trains, submarines, etc. Are there any classified equipment installed there?
Anytime this situation comes up just get up with the engineer with a code book in your hand. Say to him...” I was looking in my code book to see if I could find the reference you were making and was not able to find it...would you mind showing me where it is or getting me the article so I will know for future reference?"...
As far as flex to a transformer...that is first year apprentice stuff. Flex is used to feed small transformers for a couple reasons, one is to makes it easier to connect, disconnect, replace etc. I am not so sure I buy into the vibration theory. The transformer itself will be constructed of regular nuts and bolts for the most part.
Hard piping in a transformer is okay when you’re talking a big transformer but for a small one flex is the only way to go. If flex was not legal for connecting motors and transformers anymore it would have been heard like a shot around the world! Just think of the millions of connections that are already out there!
Just my 2 cents worth of bytes.
Regards
Greg
Common sense prevails a lot of times, not to knock any of the other responses.
There are specific ways to determine a classified location and NFPA 30 is a good place to start.
Regards
Greg
[This message has been edited by mustangelectric (edited 02-05-2005).]
