by Brianna Crandall — April 17, 2015—The National Electrical Manufacturers Association (NEMA) recently published a practical guide containing instructions for the safe and proper application of ground fault protective (GFP) devices. This standard is useful in commercial, industrial, and manufacturing applications where ground fault protective devices are applied in equipment, says NEMA.
NEMA explains that GFP devices include current-sensing devices, relaying equipment or combinations of current-sensing devices and relaying equipment or other equivalent protective equipment that will operate to cause a disconnecting means to open all ungrounded conductors at predetermined values of ground-fault current and time.
The 43-page NEMA PB 2.2-2014 Application Guide for Ground Fault Protective Devices for Equipment, developed by the NEMA 05LVDE-02-PB Technical Committee, revises and supersedes PB 2.2-1999(R2004, R2009). PB 2.2 may be downloaded at no cost or purchased in hard copy for $91 on the NEMA Web site, as can other related materials.
