DMRCD/DRCM: A Modular Concept for Residual Current Protection & Residual Current Monitoring

Light+Building: Doepke exhibits circuit-breaker and residual current meters

Norden, 9 March 2012. With its DMRCD and DRCM devices Messrs. Doepke Schaltgeräte GmbH introduces two ranges of modular residual current protection and residual current monitoring. The devices will be introduced between 15 and 20 April at the Light+Building trade fair in Frankfurt-on-Main in Hall 8.0, Stand C51. The DMRCD modular residual current circuit-breakers and the DRCM residual current monitors are VDE tested and can be utilised in electrical installations with current ratings of up to 630 amps. Their application ensures that the legal requirements in respect of protection of persons and fire protection are being met, while also offering early fault detection without disconnection. The pre-alarm facility increases equipment availability in many applications such as e.g.: industrial plant, medical-technical equipment, IT and communications technology, traffic control, power supply, event and media sectors, welding technology, agricultural applications and mechanical engineering.

Doepke’s model ranges include the DMRCD 1A and 1B+ residual current relays, which conform to the standards DIN EN 60947-2, as well as the DRCM 1A and 1B+ residual current monitoring devices, which meet all requirements of DIN EN 62020. The variants reliably identify AC residual currents as well as smooth and pulsating DC residual currents, resulting in optimum protection of persons and fire protection as well as providing for higher availability of installations.

Particularly in the main- and sub-distributions of industrial plant, Doepke’s DMRCD and DRCM offer flexible residual current protection and continual residual current monitoring with selectable pre-alarm and main alarm up to a current rating of 630 A and a voltage of 690 V of the monitored system. In other installations with high current consumption such as market distributions, construction site distributions and crane installations, the devices may also function as selective protection.

The pulsating current-sensitive combinations consisting of external transformer and control relay detect residual currents within a frequency range of 50 to 60 Hz. The ACDC sensitive detection identifies residual currents of 0 – 100 kHz. Both model ranges feature a tenfold LED display and offer setting options for the residual response current (30, 100, 300, 1000 and 3000 mA) as well as for pre-alarm and main alarm. Alarm is signalled via a red LED, flashing LEDs or via independent relay out puts.

Both model ranges also include external current transformers with differing inside diameters. Transformer connecting leads are available ready-made in lengths of 1 to 10 metres with RJ 45 plug connectors. In addition, magnetic field centering sleeves can be supplied in various sizes under the designation DMBT. Centering the magnetic field prevents partial saturation and thus spurious tripping and permits higher current ratings.