Residual current device (RCD) iID-40-4-100-A 40A 4-pole 100mA type A A9Z22440

Safety and reliability in 4-pole installations

This device is a key protection element in electrical systems, providing detection of leakage currents with a value of 100 mA. Thanks to the use of Type A characteristics, the device reacts effectively not only to AC currents but also to pulsating DC currents, making it suitable for protecting circuits with modern electronics, inverters, or devices with rectifiers. The rated load current is 40 A, allowing for safe energy transmission in circuits with medium and large consumption, such as residential building switchboards, small industrial plants, or photovoltaic installations (in appropriate configurations). A short-circuit strength of 10 kA guarantees that the device will withstand short-term current surges without permanent damage, provided that overcurrent protections act quickly.

Installation comfort and functionality for the installer

Mounting is performed on a standard DIN rail, and the device width is exactly 4 modules (72 mm), which facilitates space planning in the switchboard. The installer will particularly appreciate the ability to connect wires with cross-sections from 1 to 35 mm² (for single-core wires) and up to 25 mm² (multi-core). Such a wide range of cross-sections eliminates the need for additional ferrule connectors in many cases and allows for the direct connection of thick power cables. An additional advantage is the terminal design that enables the mounting of busbars and the possibility of removing a single device without the need to dismantle the entire busbar – this saves time during modernizations or repairs.

The device features a mechanism lock, which prevents accidental switching after a protective trip. The status indication is visually clear: the VisiTrip mechanism informs about an electrical trip (white-red indicator), and VisiSafe confirms the absence of voltage on the load side (green color), increasing safety during service work. The test button allows for periodic verification of the differential circuit's correct operation – it is recommended to perform the test once a year.

Application and resistance to environmental conditions

Thanks to the IP20 protection rating and operation in temperatures from -25 °C to +60 °C, the switch can be installed in utility rooms, garages, or unheated external switchboards (provided they are protected from direct exposure to atmospheric conditions). The rated insulation voltage is 500 V, and the impulse withstand voltage (Uimp) reaches 6 kV, ensuring high resistance to surges from the grid or atmospheric discharges. The device complies with the IEC/EN 61008-1 standard and holds a VDE certificate.

The possibility of expansion with additional auxiliary modules (e.g., undervoltage releases iMN, overvoltage releases iMSU, or auxiliary contacts iOF) allows for system integration with building automation or remote monitoring systems. Power losses are only 3.8 W, which translates to less device heating under long-term load. All key technical data – such as the 100 mA sensitivity for Type A, the 40 A rated current, or the 10 kA short-circuit strength – are an integral part of the device design and ensure its reliable operation in demanding installation conditions.