NEMA Updates Molded-Case Circuit Breaker Standard

The National Electrical Manufacturers Association recently published a new version of NEMA AB 4-2017 Guidelines for Inspection and Preventive Maintenance of Molded-Case Circuit Breakers Used in Commercial and Industrial Applications. 

"This revision contains several edits to reflect new industry practices as well as harmonize the industry standards that apply to molded-case circuit breakers,” said Patrick Salas, chair of the AB4 Task Group, and director, Codes & Standards GE Energy Connections, Industrial Solutions.

Molded-case circuit breakers have a very diverse use in several commercial and industrial applications. NEMA AB 4 is designed to guide qualified personnel during inspection and maintenance. NEMA AB 4-2017 is available for $103 in hard copy and as an electronic download at no cost on the NEMA website.