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#5371 11/18/01 01:31 AM
Joined: Oct 2000
Posts: 2,722
Scott35 Offline OP
Broom Pusher and
I have posted some details Schematics covering IG circuitry, plus one Image sent to me by a Member.

These items are found in the Technical Reference area under the topic heading of:

IG Details #1

Feel free to check them out.
If you have questions, comments, or would like to discuss these Drawings and / or IG Systems, feel free to do so within this thread.

Scott SET

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
#5372 11/18/01 09:10 AM
Joined: Aug 2001
Posts: 7,520
Interesting diagrams Scott --Thanks.

We're seeing more of this sort of thing here as well with the increasing use of computers.

We don't have the bright orange recepts. to identify IG outlets, but some manufacturers have gone as far as introducing a "non-standard" plug and socket so that equipment can be wired with different plugs and nobody can connect to the wrong outlet.

The plugs are based on our normal 13A type, but use a different shape earth (ground) pin. The only problem is revealed in the "non-standard" part of the definition: Each manufacturer has changed the pin shape in a different way, so a MK plug won't fit a Crabtree outlet, for example.

#5373 11/18/01 09:10 AM
Joined: Jul 2001
Posts: 311
Excellent job Scott. Many of my questions have been answered. Thank you.

#5374 11/18/01 11:02 AM
Joined: Nov 2001
Posts: 280
I have a question, I assume the first panel is a sub-panel because it has a neutral bus and an equipment ground bus, and you show a third bus an insulated ground buss bar for the IG.
When we do IG we feed the IG all the way thruogh to the service panel.
How do you mount the IG bus-bar in the sub-panel wiht out grounding it ?

#5375 11/18/01 11:48 AM
Joined: Oct 2000
Posts: 5,392
It would be an isolated G-bar,
see 250.146(D) 408.20EX in the 02', 384-20 in the 99' would also apply. Scott, has in past threads, expanded more than the average poster about the do's & don't of iso-installations.
I can't speak for listing standards, but i do note that there is no mention of MBJ or MDP as being the source iso-G in the NEC.
so comes the 'monkey wrench', am i in violation if i do not [Linked Image] run the iso-G back to these???

#5376 11/18/01 03:34 PM
Joined: Dec 2000
Posts: 4,289
Not at all, Steve. These recps can be grounded to the metal box that they're in, and you're not in violation. As long as you have an approved grounding path, it doesn't matter at what point you attach the ground.
Motor-T, the IG ground bus is connected in the same way the neutral bus is. (You answered your own question! [Linked Image])It's insulated from the can in the subpanel. It goes through another cable to the place where it is eventually grounded.
Cool diagrams, Scott

[This message has been edited by electure (edited 11-18-2001).]

#5377 11/18/01 08:26 PM
Joined: Nov 2001
Posts: 280
Thanks for the clarification, sorta figured that but old habits die hard.

#5378 11/19/01 10:33 PM
Joined: Oct 2000
Posts: 2,722
Scott35 Offline OP
Broom Pusher and
Thanks to everyone for the replies! I have revised the post in the Technical Reference area to include an Image sent to me from Joe Tedesco.

Scott SET.

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

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