Residual current circuit breakers (RCCBs) switch off the power supply when dangerously high residual currents occur. They thus protect people, animals and systems. DFS 2 are two-pole residual current circuit breakers for single-phase networks. In the standard version, the compact devices are two division units wide. They are available with many different residual current types and versions with rated currents of up to 125 A. The large double-deck terminals can also accommodate large conductor cross-sections. The tripped position of the multi-function switch toggle makes troubleshooting easier. The free label software helps with labeling. Type F switches are mixed frequency sensitive. They protect against pulse and alternating residual currents as well as residual currents with mixed frequencies deviating from 50 Hz, regardless of the mains voltage. They are resistant to increased surge currents and storms. Devices in the standard version are designed for monitoring circuits with a rated voltage of 230 V and a rated frequency of 50 Hz. Properties: sensitive to alternating and pulsating direct residual currents of the mains frequency (type A) as well as alternating residual currents with mixed frequencies not equal to 50 Hz, high immunity to surge residual currents and mains voltage-driven follow-on current pulses, small size for all rated currents, high short-circuit strength, double-sided double-deck terminals for large conductor cross-sections and rail connection, switch position indicator, viewing window for labelling labels, multi-function switch toggle with three positions: 'on', 'off', 'tripped', connection C1 neutral conductor position as required, mounting type: quick fastening on mounting rail, installation position as required, feed direction as required, areas of application: modern house installations with LED lighting systems and single-phase frequency converters, ideal for systems in which type A RCCBs tend to trip incorrectly due to surge residual currents, commercial and industrial installations with TN-S, TT and TN-CS systems in which power electronics equipment without galvanic mains isolation is used such as switching power supplies, high-frequency converters, photovoltaic and UPS systems with transformerless inverters. Use in TN-C networks and for protecting systems in which electronic equipment can cause smooth DC residual currents is excluded. Comprehensive protection is not provided here. For such applications, we recommend our universal current sensitive residual current circuit breakers (type B or B+). Notes: suitable for use in 50 Hz AC networks. Not intended for use in DC networks or on the output side of controlled electrical equipment such as frequency converters.