Hager RCD 40A Type A 30mA 4 Pole 4 Module CDA440U

Hager CDA440U: 40A 30mA 4 Pole Type A RCCB (residual current circuit breaker) for automatic disconnection on earth fault conditions.

Safety & Reliability

This Hager Ltd RCCB automatically opens the circuit the moment it detects an earth fault between line and earth, or neutral and earth, cutting power before a fault becomes a hazard. The Type A leakage current rating means it responds to both AC and pulsating DC residual currents, giving broader protection than a standard AC-type device on circuits with electronic loads such as inverters or variable speed drives.

A trip-free mechanism prevents the contacts from being held closed against a fault, so the RCCB can't be defeated by someone holding the operating lever. For sites needing lockout/tagout control, the unit can be padlocked either on or off using an MZN175 accessory, supporting safe isolation procedures during maintenance.

Clear Status Indication

A rectangular flag indicator shows circuit status at a glance: red for closed, green for open, and yellow when the device has tripped on a fault. This removes the guesswork on a distribution board and speeds up fault-finding, particularly useful when several RCCBs or RCCB's are installed together on the same board.

Installation & Compliance

Rated for 400V, 40A with a 6kA short-circuit withstand rating, this 4 pole unit is built to BS EN 61008 and IEC 61008, so it drops into standard consumer unit and distribution board designs without any compliance concerns. DIN rail mounting and a 4-module width keep installation straightforward on new boards or retrofits.

Terminal capacity accepts 1mm² solid or multi-wired conductors for this current rating, and the IP20 enclosure gives a basic level of finger-safe protection once installed inside a board. For sites also specifying arc fault detection, Hager AFDD devices are available to complement RCCB protection on individual final circuits.

Key Features of the Hager RCCB CDA440U Include:

• Automatically Disconnects Supply On Earth Fault Between Line And Earth, Or Neutral And Earth
• Type A Leakage Current Detection Covers Both AC And Pulsating DC Residual Currents
• Trip-Free Mechanism Prevents Override During A Fault Condition
• Rectangular Flag Indicator Shows Closed (Red), Open (Green) And Tripped (Yellow) States
• Can Be Padlocked On Or Off Using An MZN175 Accessory For Safe Isolation
• Conforms To BS EN 61008 And IEC 61008
• 4 Pole Configuration Rated 40A At 400V
• 30mA Rated Residual Operating Current
• 6kA Short-Circuit Withstand Rating (Icw)
• DIN Rail Mounting, 4 Module Width
• IP20 Degree Of Protection
• Terminal Capacity: 1mm² Solid Or Multi-Wired Conductors
• Operating Ambient Temperature Down To -25°C

If you need some help, would like to take advantage of our Price Promise or have a large order to place, give our team of professionals a call on 0203 994 5470, drop us an email at sales@electricpoint.com or use our Contact Form.