Grounding Transformer and building

[Eclair]

Hi guys

Here is the situation:
I have to ground an old 2 floor building and a new 1.5MVA transformer located behind.

Here is what I would do for the transformer:
-Belt the transfomer with a bare 4/0 copper cable.
-Ground the metal structure of the enforced concrete structure surrounding the transfomer and below the tranformer.
-Ground the metal barrier.
-Ground all this with four 10'x 3/4" copper rods at the four corner of the transformer (each one at 20' distance from another as per IEEE).
-Connect everything with 4/0 bare copper cable.

For the building:
-Surround the building with a 4/0 bare copper cable at 18" of depth with 10'x 3/4" copper rods at the four corner.
-Connect the building with the grounding system of the transformer at 2 location.

I would like to have some guidelines from you guys cause I can't find anything really useful.

I particulary need:
-depth of stone (rock) to protect the surrounding area of the transformer
-The recommanded area of ground carpet around the tranformer.

I have consulted the IEEE green book for this. It doesn't contain a lot of very useful information.

Thanks

 

[Eclair]

I would also ground each steel beam of the building structure as well...

 

[itsmoked]

Make sure thieves can't steal any of it. I'm serious! You need to include that in any design now.

Just had a bunch of cable stolen.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com