IEEE S.F. Bay Area Council e-GRID's

Technology & Networking in Silicon Valley & the SF Bay Area: Upcoming Meetings, Courses and Conferences

November 17, 2013

Mtg: Ground Fault Current Protection of a 480Y/277V Power System – Compliance with NEC Design Requirements

by @ 4:20 pm. Filed under ALL, Electrical/Power

THURSDAY November 21, 2013
OEB Power & Energy, with Industry Applications chapters
Speaker: Dev Paul, AECOM, Inc.
Time: Networking at 5:30 PM, Presentation at 6:15 PM; Dinner at 7:15 PM; Presentation continues at 8:00 PM
Cost: $25 for IEEE members, $30 for non-members, $15 for student and retired members
Place: Zio Fraedos, 611 Gregory Lane, Pleasant Hill
RSVP: by November 18 to Michael Nakamura,, 925-330-6595

Dev Paul will discuss his IEEE/PCIC 2013 Conference paper that he presented as the main author.  This paper is based upon an actual design of port facility buildings that required installation of solar power to meet the portâ??s green energy initiative.  For the building parking lots, solar panels were installed on each carport roof for generation of photovoltaic (PV) power.  Each buildingâ??s main switchboard required a 480Y/277V, 3-phase, 4-wire power supply based upon the characteristics of the building loads and parking lot lighting system.  The presentation will cover the following key project considerations:
�    Low-level arcing ground fault protection of building transformer secondary feeders to main switchboards and discussion of ground fault protection of equipment, NEC 230.95.
â?¢Â Â   Connection of PV utility-interactive DC-AC inverters to buildingsâ?? service switchboards and discussion of the switchboard bus rating, NEC 705.12.D. (2) and NEC 705.12.D. (7).
�    Although the design solution of a low-level ground-fault current protection on transformer secondary feeders is contained in NEC 240.92(C) (1) (2) Informational Note No.1, quite often in the design the implementation of a differential relay, device 87T, indicated in NEC, is overlooked by the design engineers and AHJ that approve the design. Discussion of technical issues of such protection and dealing with the utility company if power transformer is supplied by utility company will be discussed.
â?¢Â Â   Transformer secondary feeder cablesâ?? short-circuit current withstand capability that depends upon short-circuit fault clearing time by the transformer primary protection device will also be discussed. Although NEC Table 240.92 (B) describes the method of checking such requirements, but quite often design engineer may have difficulty, especially when transformer and secondary cables are by the utility company.
â?¢Â Â   Fire Incident â?? Lack of transformer secondary ground fault current protection will also be presented.
This presentation will be very helpful for the design engineer involved in complying with NEC requirements and also meeting most recent electrical arc-hazard and coordinated ground fault protection.


Comments are closed.

[IEEE S.F. Bay Area Council -] [powered by WordPress .]

SF Bay Area Council


  • 5G (2)
  • ALL (4,702)
  • Antennas & Propagation (5)
  • BioEngineering (675)
  • Blogroll (33)
  • Circuits (16)
  • Communications (1,862)
  • Computers/Software (1,777)
  • Consumer Electronics (103)
  • Control Systems (23)
  • Electrical/Power (1,284)
  • Electronics Design (2,774)
  • Employment (4)
  • Employment opportunities (7)
  • Engineering Mgmt (1,819)
  • Green energy (48)
  • History (7)
  • Industrial Applications (91)
  • Information Theory (13)
  • Instrument and Measurement (1)
  • Magnetics (30)
  • Microwave (8)
  • NanoEngineering (876)
  • Optics/Displays (969)
  • Photonics (31)
  • PhotoVoltaics (4)
  • Product Safety (25)
  • Reliability (37)
  • Robotics and Automation (19)
  • Semiconductors (1,847)
  • Signal Processing (138)
  • Vehicular Technology (16)
  • Women in Engineering (8)
  • Young Professionals (5)

    Support our advertisers:

    Visit our

    Enabling Javascript allows us to show you upcoming conferences in this column.

    For the Firefox browser, select Tools/Options/Content and select "Enable Javascript".

    If you are using Microsoft Internet Explorer you may need to click on the yellow bar above and select 'Allow Blocked Content'. You must then click 'Yes' on the following security warning.


    August 2019
    S M T W T F S
    « May    

    View in Google Calendar

    search blog:

    SUBSCRIBE: Get the e-GRID twice a month by email - upcoming IEEE SF Bay Area meetings, conferences.

    RSS Feed Subscribe to our RSS Feed.

    PUBLICIZE your event to IEEE's membership.

    general links:

    22 queries. 0.437 seconds