Siemens ED42B090 Two Pole Molded Case Circuit Breaker

Siemens ED42B090 is a two-pole molded-case circuit breaker from the Sentron ED4 family, designed for low-voltage distribution and protection of feeders and branch circuits. It is rated at 90 A and 480 VAC, with an 18 kA interrupting capacity at 480 VAC, providing robust short-circuit protection for commercial and industrial panels. The device uses a thermal-magnetic trip unit to provide both overload and instantaneous protection, and it comes standard with load-side lug terminals for direct connection to conductors. The ED42B090 is an ED-frame MCCB, and its ratings also include a 250 VDC capability, allowing use in systems that switch DC loads alongside AC. As a 2-pole breaker, it interrupts both conductors simultaneously, helping maintain safe and balanced distributions in 480 V networks. This specific ED42B090 variant is configured with load lugs, which is common for panelboard installations where the breaker is mounted in a Siemens ED4-compatible enclosure. When selecting protective devices for Siemens ED panels, ED4-series breakers like the ED42B090 are specified for circuits at or near 90 A, ensuring coordinated protection with compatible upstream devices and downstream loads.