ECM Buyers' Guide

Code Q&A

Feb 7, 2008 2:41 PM, By Mike Holt


         Subscribe in NewsGator Online   Subscribe in Bloglines     

Q. What are the Code requirements for bonding bushings on 277V or 480V branch and feeder and circuits?

A.Metal raceways or cables containing 277V and/or 480V branch or feeder circuits terminating at ringed knockouts must be bonded to the metal enclosure with a bonding jumper sized in accordance with 250.122, based on the rating of the circuit overcurrent device [250.102(D)]. A bonding jumper isn’t required where ringed knockouts aren’t encountered or where the box is listed to provide a reliable bonding connection as in a typical 4 square outlet box [250.97].


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