ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Recent Posts
Do You Wrap Your Receptacles?
by gfretwell - 02/20/24 10:48 PM
Cable Chase Code Requirement
by renosteinke - 02/16/24 07:00 PM
Do we need grounding?
by gfretwell - 02/16/24 10:37 AM
Cordless Tools: The Obvious Question
by gfretwell - 02/08/24 07:28 AM
Is this really a thing
by renosteinke - 02/07/24 01:15 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
1 members (Scott35), 65 guests, and 26 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Joined: May 2002
Posts: 202
which section in the code will cover this and explain. please there are some different views at work and would like to clear this up. some are just hooking a ground to the metal case, others are tying X1 to ground and grounding the case. I have seen it done both ways or not at all. note these are typical 480V to 120 V

[This message has been edited by jlhmaint (edited 09-04-2002).]

Stay up to Code with the Latest NEC:

>> 2023 NEC & Related Reference & Exam Prep
2023 NEC & Related Reference & Study Guides

Pass Your Exam the FIRST TIME with the Latest NEC & Exam Prep

>> 2020 NEC & Related Reference & Study Guides

Joined: Jul 2002
Posts: 175
I can't quote code rules, as I do not know the NEC well enough, but the basic principles of grounding and bonding are similar everywhere.

The sketch below shows grounding and bonding for a typical single phase stepdown transformer.

[Linked Image from]


Joined: Nov 2000
Posts: 2,148
These are Separately Derived Alternating-Current Systems as covered in 250.30. Eds drawing is right on the mark.

Joined: May 2002
Posts: 202
ok that pic shows exactly how we do it in our building but we have seen some from our other building that were not like that or no ground or bond at all. Thanks

Joined: Apr 2002
Posts: 2,527
I may be missing something, but don't {99NEC} 250-30 and 250-26 fairly well cover the matter? The sizes listed are all above 1000VA. Probably one aspect of the ‘building steel’ versus “case” ground, it would seem more critical if the wiring runs extended out of a local area. [In the case of an open secondary bonding jumper, it’s maddening to have to do much troubleshooting on ungrounded 120V controls.]

Link Copied to Clipboard

Tools for Electricians
Tools for Electricians

* * * * * * *
2023 National Electrical Code (NEC)
2023 NEC + Exam Prep Study Guides Now Available!
* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Member Spotlight
Posts: 201
Joined: April 2004
Top Posters(30 Days)
maxecn 5
Admin 3
Popular Topics(Views)
317,976 Are you busy
242,888 Re: Forum
226,884 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5