Residual-current circuit breaker Eti-Polam KZS-4M 4P 16A B 30mA type AC (002174004)

Eti-Polam KZS-4M 4P 16A B 30mA type AC is a combined residual-current device (RCD) and miniature circuit breaker (MCB) designed for three-phase electrical installations. This 4-pole unit provides overcurrent protection with a B-type tripping characteristic at a rated current of 16 A and detects sinusoidal alternating leakage currents with a residual sensitivity of 30 mA. The device is intended to reduce the risk of electric shock and to protect wiring and equipment from overloads and short circuits in residential and light commercial distribution boards.

Advantages

The combined RCD+MCB structure integrates earth-leakage detection and overcurrent protection in a single compact module, saving space in distribution panels and simplifying wiring. The B characteristic ensures timely tripping on moderate short-circuit and overload conditions typical in lighting and general-purpose circuits. AC-type residual current detection reliably senses pure sinusoidal leakage currents, making the device suitable for conventional installations without electronic leakage components. The four-pole design enables comprehensive protection in three-phase systems, including neutral disconnection, which helps maintain safety across all conductors.

Suitable for

• Protection of three-phase circuits in residential distribution boards
• Light commercial and small workshop installations
• Feeder circuits supplying lighting, socket outlets and small motors
• Applications requiring both overcurrent and earth-leakage protection in one device

Key specifications

• Poles: 4-pole (three phases plus neutral)
• Rated current: 16 A
• Tripping characteristic: B curve (magnetic-electrical trip for moderate fault levels)
• Residual current sensitivity: 30 mA
• Residual current type: AC (detects sinusoidal alternating leakage)
• Function: Combined residual-current device and miniature circuit breaker
• Mounting: DIN-rail compatible housing for distribution boards

How to use

Install the Eti-Polam KZS-4M in the distribution board on a standard DIN rail, connecting the three phase conductors and neutral to the corresponding input and output terminals according to wiring diagrams and local regulations. Ensure the device is fitted upstream of the circuits it is intended to protect. Before commissioning, verify correct wiring polarity, torque terminal screws to manufacturer-recommended values, and test the device using a residual current tester or the built-in test mechanism where available. Replace or service the unit only when the supply is isolated and by qualified personnel.

Usage recommendations

Use this device where protection against electric shock and combined overload/short-circuit protection are required in three-phase installations. Verify compatibility with downstream equipment, avoid connecting loads with electronic leakage characteristics that require type A or type B residual current detection, and perform periodic testing of residual current operation as part of routine electrical maintenance.