ECM Buyers' Guide

Code Q&A

Nov 27, 2007 3:58 PM, By Mike Holt


         Subscribe in NewsGator Online   Subscribe in Bloglines     

Q. A single main breaker is installed, then taps supply individual meters with disconnecting means for individual tenants. Should a main bonding jumper be installed at the single main breaker or at each separate disconnect?

A. An un-spliced main bonding jumper complying with 250.28 must be installed between the grounded neutral terminal and the metal parts of the service disconnecting means enclosure in accordance with 250.24(C) [250.24(B)]. Remember that the service equipment is the one to six disconnects connected to the load end of service conductors intended to control and cut off the supply to the building or structure [Art. 100, Service Equipment]. The service you described ends at the load side of the single main breaker. The answer to your question is to install the main bonding jumper at the main breaker, and nowhere else.


Acceptable Use Policy
blog comments powered by Disqus

Want to use this article? Click here for options!

what's wrong here?

What's Wrong Here?

Jul 2, 2009 6:51 PM

What's Wrong Here?

Jun 18, 2009 4:01 PM

What's Wrong Here?

Jun 4, 2009 1:26 PM

View all What's Wrong Here?

Recent Comments

Follow comments on ecmweb.com

i-Gard contest
Here’s your chance to win $5000! All you have to do is submit a case history based on your or your client’s experience (positive or negative) in applying HRG technology to an existing or new power distribution system.
EC&M White Papers
Protecting Generators through Hybrid Grounding
The industry has recently become aware of the problem of severe generator damage due to stator ground faults. Two factors have been identified as contributors to this growing problem
EC&M TV

Retrofit 2-Gang TV Box(TM)

Arlington’s recessed two-gang TV BOX™ for old work allows you to mount LCD and plasma TVs, and other system components flush against the wall...

Hybrid Grounding - The industry has recently become aware of the problem of severe generator damage due to stator ground faults. Join us for this live webinar!

Arc Flash HazardThe 3 As of Arc Flash - Awareness, Analysis, Action

resources

product info icon

product info

tradeshow icon

tradeshow

research icon

research

rss icon

rss

Browse Back Issues

Browse Back Issues