Hager ADA920D Residual Current Circuit Breaker with Overcurrent Protection 2P 20A B 30mA Type A

The Hager ADA920D is a professional-grade residual current circuit breaker with overcurrent protection (RCBO), engineered to provide comprehensive safety for modern electrical systems. This 2-pole device integrates both short-circuit and overload protection with earth leakage detection in a single compact unit, ensuring reliable performance in residential and commercial environments. Designed for 240V AC systems, it offers a 20A rated current and a B-curve tripping characteristic, making it an essential component for safeguarding circuits against electrical faults.

Advantages

The primary advantage of the Hager ADA920D is its ability to combine two critical safety functions into one space-saving device, which simplifies installation and reduces the amount of space required in a distribution board. By utilizing Type A sensitivity, this RCBO is capable of detecting both AC and pulsating DC residual currents, providing a higher level of protection compared to standard AC-type devices. Its robust construction ensures long-term operational stability, while the precise B-curve tripping characteristic allows for optimal protection of general-purpose circuits by responding quickly to overcurrent conditions.

Suitable for

• Residential electrical distribution boards
• Commercial office lighting and power circuits
• Protection of final circuits against earth leakage and overcurrent
• Systems requiring Type A residual current detection

This device may not be suitable for industrial applications involving high-power machinery with significant inrush currents, as the B-curve tripping characteristic is specifically calibrated for standard residential and light commercial loads. It is also not intended for use in DC-only electrical systems or environments where the supply voltage significantly exceeds the rated 240V AC specification.

Key specifications

• Rated current: 20A
• Tripping characteristic: B-curve
• Sensitivity: 30mA
• Type: A
• Number of poles: 2P
• Rated voltage: 240V AC

The Hager ADA920D should be installed by a qualified electrician in accordance with local electrical regulations. The device is mounted onto a standard DIN rail within a distribution enclosure. Ensure that the supply cables are correctly terminated into the input terminals and that the load is connected to the output terminals, maintaining proper polarity and torque settings as specified by the manufacturer to ensure a secure electrical connection.

What to consider before purchase

• Verify that the 20A rating matches the requirements of your specific circuit load
• Ensure the distribution board has sufficient DIN rail space for a 2-pole RCBO
• Confirm that the Type A sensitivity is appropriate for the equipment connected to the circuit
• Check that the supply voltage is compatible with the 240V AC rating

For optimal safety and performance, it is recommended to perform a functional test of the RCBO using the integrated test button at regular intervals to ensure the mechanical tripping mechanism remains in good working order.