Residual current device ETI EFI-4 100/0.3 Type AC 10kA (2062155)

ETI EFI-4 is a residual current device designed to detect leakage currents and disconnect the circuit when a dangerous differential current appears. It is intended for use in distribution boards of residential, commercial, and other electrical installations where protection of people and equipment is required in the event of insulation damage or accidental contact with live parts. The device belongs to the RCD category and is suitable for AC networks with a rated voltage of 400 V. This model has a 3+N pole configuration, so it is designed for three-phase circuits with a neutral conductor. The rated current is 100 A, while the residual operating current is 0.3 A. Type AC means the device responds to sinusoidal alternating residual current, which is typical for standard AC electrical networks. The rated short-circuit current Inc is 10 kA, which is an important parameter for operation in systems where high fault currents may occur. The device complies with IEC/EN 61008. Mounting is performed on a TH 35 DIN rail, which makes installation convenient in standard modular distribution boards. The housing depth is 68 mm, so the device can be placed in compact switchboard assemblies while taking the available installation space into account. The rated conductor cross-section is 1 to 35 mm², allowing connection to commonly used power cables and wiring for high-load circuits. The IP20 protection rating indicates that the device is intended for installation inside electrical enclosures, where basic protection against contact with live parts is provided. EFI-4 is used as part of a circuit protection system where prompt disconnection in the event of leakage current is required. Its technical parameters make it suitable for three-phase installations with neutral, where continuous operation must be combined with protection against insulation faults and other leakage-related hazards.