Siemens 5SY42-C2 Miniature Circuit Breaker

Siemens 5SY42-C2 Miniature Circuit Breaker is a two-pole protective device for 400 V AC circuits, rated for 2 A nominal current to guard branch circuits from overload while providing defined interruption during fault conditions in commercial and light-industrial installations, with a compact footprint that helps maximize space in control panels. Built to the 5SY4 family specification, it uses a C-curve tripping characteristic and offers a short-circuit breaking capacity of 10 kA (Icn) at 400 V, enabling reliable fast isolation of faults without excessive nuisance tripping during normal startup surges and routine operation. The catalog entry for this model is 5SY4202-7, a 2P unit rated for 400 V and 2 A, with a C-curve characteristic and a mounting depth of 70 mm, aligning with Siemens' LV miniature breakers designed for standard distribution boards and modular enclosures. This MCB is intended to protect a wide range of branch circuits, including lighting and general-power loads, in controlled electrical panels where space is at a premium and predictable, repeatable tripping behavior is required to maintain system reliability and safety.