The residual current relays of the DER4 Dossena range can be used on LV networks in alternating current of the TT and TN type.
They make it possible to achieve adequate selectivity and residual current protection thanks to the wide regulation of the leakage current threshold (up to 30A) and of the trip delay threshold (up to 5s).
The Dossena DER4s are fully compliant with the strict regulations in force (CEI EN 60947-2019) thus satisfying a double need: system safety and service continuity.
Technical features:
Type A
Compliance with product standard CEI-EN 60947-2:2019
Power supply 115/230/400Vac or 24÷60Vdc
Threshold adjustment of the rated differential tripping current I∆n from 0.03÷30A
Intervention delay adjustment settable from instantaneous to 5s.
Differential current measurement in TRMS
1 intervention threshold (Trip)
Output 1 changeover contact NO-C-NC (NO 250Vac 5A P.F.1 / 30Vdc 5A - NC 250Vac 3A P.F.1 / 30Vdc 3A)
Diagnostics on the connection and operation of the opening coil
Diagnostics on connections, continuity of the toroidal transducer windings
Internal self-diagnostics, processor overtemperature control and correct functioning of the electronic circuitry