Mike Dolt Enterprises
Mike Dolt Enterprises
User: gpwilson62, Location: Reston VA
Asked on: Wednesday, April 6, 2011 at 11:44 am EDT
Answered on: Tuesday, May 14, 2024 at 3:51 am EDT
Question: Unfortunately I do not have a copy of 2011 NEC in front of me. Does 2011 NEC address the issue of backfeeding onto commercial lines from emergency generators in residential applications. Does it require either a manual or automatic xfer switch, or a way to disconnect SEC to prevent backfeeding and causing a safety hazard for linemen. if so what is the appropriate code reference. The 2005 NEC which I do have copy of allows exception for these 702.6 (ex) and I am trying to find out whether this has changed to require safety protection preventing backfeeding in the 2008 or 2011. Thanks
2011 NEC
Yes, the 2011 NEC addresses the issue of backfeeding onto commercial lines from emergency generators in residential applications.
Code Reference
701.7(C)Requirement
Requires an
automatic transfer switch (ATS) or other approved means to prevent backfeeding onto the commercial lines.
Note
The 2005 NEC exception you referenced (702.6 Exception) has been removed in the 2011 NEC. All emergency generators installed in residential applications now require an ATS or other approved means to prevent backfeeding.
Purpose: To prevent safety hazards for linemen and other electrical workers who may be working on the commercial lines. Backfeeding can energize lines that are normally de-energized, creating a dangerous situation for those working on the lines. Flag for review