transformer grounding/bonding

[inspclh]

I am looking for some simple diagrams showing proper ways of grounding and bonding transformers and separately derived systems--please help--pictures are worth a thousand words!

 

[George Stolz]

There are a lot of good diagrams in Mike Holt's free bag of tricks, click here to see all available.

Be sure to scroll down a ways, there are several 250.30 pictures, they're just not grouped. If you press and hold Cntl-F on your keyboard, and then type in 250.30 it will find them all for you.

 

[RayS]

thanks for the tip, George!

 

[mikehughes8]

looking at that picture, it only shows a groundong electrode at the bonding location. I was under the impression that grounding electrodes were required at both locations whether there was bonding or not on a SDS.

 

[George Stolz]

I was under the impression that grounding electrodes were required at both locations whether there was bonding or not on a SDS.

Incorrect, see 250.30(A)(3):

(3) Grounding Electrode Conductor, Single Separately Derived System. A grounding electrode conductor for a single separately derived system shall be sized in accordance with 250.66 for the derived phase conductors and shall be used to connect the grounded conductor of the derived system to the grounding electrode as specified in 250.30(A)(7). This connection shall be made at the same point on the separately derived system where the system bonding jumper is installed.

 

[shockme77]

This connection shall be made at the same point on the separately derived system where the system bonding jumper is installed.

Nevermind.

Thought this was a discussion about generators and I made a comment about bonding of the neutral to the frame of the genny. Like I said, nevermind.