Hello, im looking for advice on a dorman smith sensel SRD earth leakage relay. I am doing an EICR on a caravan park, the Earthing system is TT and a sensel SRD relay fitted to load side of 200 amp main switch feeding various pillars. Relays have 4 settings from 30mA to 2000mA with time delay also, is this recognised as an RCD as required as I cant achieve RCD trip times from this, maybe faulty, should a 3 phase RCD time delay be installed. Thanks