ETI EFI-4 residual current device 80/0.3 A type A 10kA (2064545)

ETI EFI-4 is a residual current device designed to protect electrical circuits against leakage currents and reduce the risk of electric shock in residential, commercial, and industrial distribution boards. It is used in AC networks where differential current monitoring is required, while overcurrent protection is provided by other devices in the installation. Compliance with IEC/EN 61008 confirms that this device belongs to the category of residual current protection equipment intended for standard modular distribution systems. The unit is rated for a nominal current of 80 A and a residual operating current of 0.3 A. Such parameters make it suitable for circuits where controlled leakage monitoring is needed at a higher current level, including supply lines in larger low-voltage installations. Type A means the device responds not only to sinusoidal alternating residual current, but also to pulsating direct residual current, which expands its applicability in circuits with electronic loads. The 3+N pole configuration indicates use in three-phase four-wire systems with a neutral conductor, allowing the device to be integrated into networks that require simultaneous monitoring of all active conductors. The device is designed for mounting on a TH 35 DIN rail, which simplifies installation in switchboards and enables convenient arrangement together with other modular components. The body depth is 68 mm, an important factor when planning the internal layout of the enclosure and the available installation space. The permissible conductor cross-section for connection is 1 to 25 mm², which supports a wide range of wiring solutions for power circuits. The rated short-circuit current Inc is 10 kA, and the nominal AC voltage is 415 V at 50/60 Hz, which defines its use in three-phase distribution systems with standard industrial and commercial operating conditions. With IP20 protection, the device is intended for installation inside enclosed electrical panels where direct contact with live parts is prevented by the cabinet structure. Overall, ETI EFI-4 is a functional choice for differential protection in installations that require defined electrical ratings, modular DIN-rail mounting, and compatibility with three-phase networks with neutral.