KZS-1MS: Compact, Voltage-Independent Protection in One Module
The KZS-1MS is one of the first electromechanical (voltage-independent) residual current circuit breakers with overcurrent protection (RCBO) on the EN/IEC market available in only one modular width.
RCBOs combine residual current detection, short-circuit, and overload protection in a single device, providing both electric-shock protection and line protection. This all-in-one solution enhances reliability, improves system availability, and simplifies installation planning.
KZS-1MS stands out with its compact design, mechanical endurance of up to 10,000 operating cycles, and switching capacity of 6 kA according to EN 61009-1. Its energy limitation class 3 ensures minimized let-through energy, contributing to better protection of connected equipment.
Thanks to its electromechanical operation, the device remains fully functional even in the event of a supply voltage failure, guaranteeing consistent protection performance. Designed for flexibility, it allows top or bottom power supply connection and supports a wide temperature range from –25 °C to +40 °C.
Additional advantages include:
Voltage-independent operation – maintains full protection even when the supply voltage is lost, ensuring maximum reliability.
Compact 1-module design – combines three protection functions in the space of a single device, freeing up valuable DIN-rail space.
Optimized energy limitation – minimizes thermal and mechanical stress on cables and connected equipment.
Flexible installation – power supply possible from top or bottom, suitable for various wiring configurations.
KZS-1MS – compact, reliable, and always ready to protect.
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