Residual Current Circuit Breaker Schneider K60 A9Z05425 — 25A 4-pole 30mA Type AC

Schneider K60 residual current circuit breaker A9Z05425 is a 4-pole device rated for 25 A with 30 mA sensitivity, Type AC. It is designed to detect alternating residual (earth leakage) currents and disconnect supply to reduce the risk of electric shock and fire. The unit is intended for installation in residential and light commercial distribution boards where AC-only RCD protection is required and integrates with standard DIN-rail mounting electrical switchgear.

Advantages

The K60 offers reliable AC residual-current detection with a clear rated sensitivity of 30 mA and a straightforward 4-pole configuration for three-phase plus neutral circuits. Its 25 A rated current makes it suitable for a range of final circuits and small distribution systems. The Type AC characteristic provides stable operation for alternating sinusoidal leakage currents, and the compact design supports installation in typical consumer units and distribution boards.

Suitable for

• Protection of three-phase with neutral circuits in residential and small commercial installations
• Circuit protection where alternating residual currents (Type AC) are expected
• Distribution boards and consumer units using DIN-rail mounted modular devices
• Applications requiring coordinated overcurrent devices rated around 25 A

When it may not be suitable

This device is Type AC and detects only alternating residual currents; it does not provide protection against pulsating DC residual currents or smooth DC components. For installations where DC leakage, frequency converters, solar inverters, electric vehicle chargers, or other equipment produce residual currents with DC components or high-frequency signatures, a Type A, Type B or specific selective RCD should be considered instead.

Key specifications

• Rated current: 25 A
• Poles: 4 (three-phase plus neutral)
• Residual operating current (sensitivity): 30 mA
• Residual current type: AC (sensitive to alternating sinusoidal residual currents)
• Intended mounting: DIN-rail modular distribution boards

How to use

Install the Schneider K60 RCD on the distribution board DIN rail ensuring correct orientation and secure mechanical mounting. Connect the three phase conductors and neutral to the corresponding input and output terminals following local wiring regulations and the device’s terminal markings. Verify correct upstream and downstream coordination with overcurrent protection devices (breakers/fuses). After wiring, perform an installation test: check continuity of protective conductors, switch on the supply, and use the device’s test function or appropriate test equipment to confirm trip at or near 30 mA sensitivity. If required by local codes, document test results and label the protected circuits.

What to consider before purchase

• Confirm that Type AC protection is appropriate for the connected loads and that no DC leakage sources are present
• Verify that 25 A rated current matches the load and downstream protective devices
• Ensure space and DIN-rail compatibility within the intended distribution board
• Check local electrical codes for required RCD types and coordinated protection

Usage recommendations

Use the K60 RCD for final circuit protection where alternating residual currents are the expected hazard, pair it with appropriately rated MCBs for selective coordination, and perform periodic test-button checks or professional testing to maintain protective function.