Earth leakage differential relay
max. 30 A, max. 4 s | 1RDT30E - A
Revalco
Earth Leakage control and monitoring consist of a Current Relay and associated Summation Toroidal Current Transformer which are used in LV
networks with alternating current in TT, IT, and TNS systems. They provide the protection required against indirect contacts, (complementary protection
against direct contacts)and against the risk of fire ( as the low currents through the earth are not enough for to let the magnetothermic device
intervene). The standard CEI 64.8 says that the earth leakage relay is considered as additional protection therefore not an unique device for
protection against the direct contacts. Ali cables of a single or three phase system, including the neutral where present, must cross the toroid which is
the point of residuai current,the device activates when it detects detective insulation which is indicated when the vectorial sum of the current carrying
cables results in a differential figure.Referring standards: CEI EN 60947.2/B paragraph B.8.2.
