E-Frame Circuit Breaker

Square D by Schneider Electric Equipment Protection Device (EPD) circuit breakers are designed with ground fault protection. The ground fault protection level is fixed at 30 mA per UL 1053 and is designed to protect equipment from damage. More than 90% of short-circuits initially involve ground faults. Detecting ground faults before they reach hazardous levels helps to avoid damage to expensive electrical equipment. This allows preventative maintenance to be scheduled before damage occurs.

E-frame circuit breakers are 1-, 2- or 3-pole thermal-magnetic circuit breakers that mount in Square D NF circuit breaker panelboards. Continuous current ratings of 15, 20, 30, 40 and 50 A are available with a wide range of interrupting ratings. An EPD compares the outgoing load currents with returning currents to determine if there is leakage of current to ground. If it detects a ground fault greater than 30 mA, the EPD will trip and display the “red flag” of the VISI-TRIP indicator. The National Electrical Code (NEC) permits the use of an EPD for heat trace as a means of preventing freezing of pipes, rain gutters, etc. Other applications include protection of well pumps and other electrical equipment.