Siemens 5SY4125-7 Auxiliary Circuit Switch Module

Siemens 5SY4125-7 Auxiliary Circuit Switch Module is a 1-pole miniature circuit breaker designed for 230/400 V systems, rated 25 A with a C-type tripping characteristic and a 10 kA short‑circuit breaking capacity, housed in a compact enclosure with a mounting depth of 70 mm and IP20 protection. This unit comes with an auxiliary circuit switch accessory (5ST3010AS) installed, providing a single auxiliary contact to signal the breaker’s position for control logic and monitoring. It’s well-suited for integration into Siemens modular switchgear and control panels where both protection and status signaling are required, such as feeders to small motors or control circuits in industrial automation. The device follows standard Siemens mounting interfaces and is compatible with 5SY breakers and 5ST3 auxiliary components, enabling straightforward panel installation and interconnection with other automation hardware. Operating voltage remains 230/400 VAC, with a 25 A rated current, type C characteristic, and a 10 kA breaking capacity, all within an IP20 enclosure suitable for indoor installations; the 70 mm depth supports compact panel layouts while delivering reliable overcurrent protection for downstream devices.