Residual current breaker HiSmart NV821945 25A 30mA

Residual current circuit breaker HiSmart NV821945 combines overcurrent protection and earth-leakage detection in a single 4-pole device. Rated for 25 A and a residual operating sensitivity of 30 mA, this RCBO disconnects circuits quickly on leakage or overcurrent to reduce the risk of electric shock and fire. It is designed for DIN-rail EN 60715 (35 mm) installation and fits residential and light-commercial electrical installations.

Advantages

The device offers combined protection against overloads, short circuits and earth faults, with C-class tripping characteristics and a rated short-circuit capacity of 6 kA. It features an anti-mistake contact terminal block, clear contact position indication (red = closed, green = open), flame-retardant and high-temperature resistant housing, and supports cable or pin-type busbar connections up to 35 mm².

Suitable for

• Protecting household circuits on DIN-rail installations
• Light commercial electrical panels requiring combined RCD and MCB protection
• Circuits where 30 mA sensitivity is required for personal protection

Key specifications

• Number of poles: 4
• Rated current (In): 25 A
• Tripping class: C
• Rated residual sensitivity: 30 mA
• Rated voltage (Ue): AC 230 V
• Rated short-circuit capacity (Icn): 6000 A
• Rated impulse withstand voltage (Uimp): 4000 V
• Insulation voltage (Ui): 500 V
• Frequency: 50/60 Hz
• Break time: <= 0.1 s
• Mechanical life: 10000 operations; electrical life: 4000 operations
• Connection type: cable or pin-type busbar (top connection), up to 35 mm²
• Protection class: IP20
• Installation: DIN-rail EN 60715 (35 mm)
• Operating temperature: -25°C to +70°C
• Dimensions: 82 × 72 × 78 mm
• Standards: IEC 61009-1 / EN 61009-1

How to use

Mount the HiSmart NV821945 on a 35 mm DIN rail and connect supply and load conductors to the top terminals following polarity and local wiring regulations. Ensure cable or busbar cross-sections do not exceed 35 mm² and tighten terminals to the manufacturer’s recommended torque. Verify correct operation by performing a test trip after installation and before putting the circuit into service.

Recommendations

Use this RCBO for circuits requiring combined overcurrent and earth-leakage protection; test the device periodically and replace it if it fails a functional test. Observe national electrical codes and manufacturer instructions during installation and maintenance.