Residual Current Breaker HiSmart NV821938 4P 20A 30mA

Residual Current Breaker HiSmart NV821938 is a 4-pole RCBO rated at 20 A with 30 mA residual sensitivity. It combines overcurrent (class C) and earth-leakage protection in a single device to detect leakage currents and disconnect supply, reducing the risk of electric shock and fire in residential and light commercial installations. The unit is designed for DIN-rail mounting and supports cable or pin-type busbar connections.

Advantages

This HiSmart NV821938 RCBO provides combined protection against overloads, short circuits and earth leakage with a breaking capacity of 6 kA. Features include an anti-mistake contact terminal block, flame-retardant and high-temperature resistant housing, impact resistance, and clear contact-position indication (red = closed, green = open). It supports top connection and accommodates conductors or busbars up to 35 mm².

Suitable for

• Residential electrical distribution boards requiring 4-pole protection
• Small commercial installations where 30 mA earth leakage sensitivity is needed
• Circuits that require combined overcurrent (class C) and residual-current protection

Key specifications

• Number of poles: 4
• Rated current (In): 20 A
• Trip characteristic: Class C
• Rated 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: 10,000 operations; Electrical life: 4,000 operations
• Protection rating: IP20
• Connection type: cable / pin-type busbar, top connection
• Wire/busbar cross-section: up to 35 mm²
• Mounting: DIN rail EN 60715 (35 mm)
• Operating temperature: -25 °C to +70 °C
• Dimensions: 82 x 72 x 78 mm
• Standards: IEC 61009-1 / EN 61009-1
• Warranty: 24 months

How to use

Install the HiSmart NV821938 on a standard 35 mm DIN rail according to local electrical codes. Make top connections using appropriate cables or a pin-type busbar, ensuring conductor cross-sections do not exceed 35 mm². Verify correct polarity and tighten terminals to the manufacturer’s torque specifications. Use the contact-position indication to confirm the device state (red = closed, green = open) and test the unit after installation to ensure correct tripping at leakage currents.

Recommendations

Mount and commission this RCBO only by qualified personnel. Periodically test residual-current operation according to local regulations and the manufacturer’s instructions to maintain protection performance.