Transformer Connections

[cdpinb]

I have always had a flex connection on transformers when I connected them, I have a electrician arguing the point that you can hard pipe in a transformer, I cannot find anything in the code book to argue this point. Any Help?

 

[GoldDigger]

I have always had a flex connection on transformers when I connected them, I have a electrician arguing the point that you can hard pipe in a transformer, I cannot find anything in the code book to argue this point. Any Help?

A major reason for using flex, sanctioned by NEC is to reduce transmitted vibration. If that is not a concern,you can hard pipe it if you want.

 

[templdl]

I have always had a flex connection on transformers when I connected them, I have a electrician arguing the point that you can hard pipe in a transformer, I cannot find anything in the code book to argue this point. Any Help?

You can use pipe. Is it a good idea? No. As a competent electrician what is allowed verses what you should do is the issue. Noise transmission. The natural him of a transformer will be conducted along the pipe to the point that it is first secured away from the tranfarmer causing the hum from the transformer to eminate from that point. Is pipe a good idea even though it is code compliment?
Using flex is a much better choice.
Noise has been one of the biggests issues that I have received from my customers. If rigid or EMT conduit is used a wall has the ability to amplify the transformer noise. Depending upon the ambient noise present that transform noise can become very noticeable.

 

[kwired]

Nothing prohibits "hard piping" it.

One could argue that flex wouldn't be allowed for anything if some of the language in certain articles did not include things like "preventing transmission of vibration" or "where flexibility is required".

 

[templdl]

One is an opinion the other is not, I.e. 'required' is not an opinion but a dirctive vs what the magnetude of vibration is which is an opinion. I'm not critsizing opinion but each one of us has our definition which is very often different that others.