Circuit breakers with residual current protection (CBR) switch high currents, protect equipment, cables and lines from overcurrent and people from electric shock. DFL 8 are compact devices with an integrated auxiliary switch and connection terminals for large cable cross-sections. Type A switches are sensitive to pulse and alternating current. This function is independent of the mains voltage. With switches of this variant, the fault response current can be individually set in stages to suit the respective application (0.3 A, 0.5 A, 1 A, 3 A). The limit non-response time can also be set in stages accordingly. This makes it possible to implement a selective residual current protection circuit in systems with staggered distributions. Devices in the standard version are designed for monitoring circuits with a rated voltage of 400 V/690 V and a rated frequency of 50 Hz. Properties: adjustable rated residual current, rated currents from 100 A to 250 A, four-pole, rated voltage 400 / 690 V AC, residual current detection for alternating and pulsating direct residual currents, functional range of the residual current tripping 0 - 690 V, functional range of the residual current test device 280 - 690 V, mains and auxiliary voltage independent tripping in the event of overcurrent and residual current, high short-circuit switching capacity, connection terminals up to 185 mm2, thresholds for instantaneous and delayed overcurrent tripping adjustable, auxiliary switch integrated, type of installation: fastening on mounting plate, installation position optional, feed direction optional, areas of application: staggered power supply systems with TN-S, TT and TN-CS networks with high short-circuit power in purpose-built buildings and industry, in IT networks, the residual current tripping of the CBR can be provided for shutdown in the event of a second earth fault, the Use for residual current protection in TN-C networks. Notes: In systems whose electronic equipment can cause smooth DC residual currents or residual currents with frequencies other than 50 Hz, the CBR Type A does not provide comprehensive protection. For such applications, we recommend our universal current sensitive CBR Type B.