Dear Friends,
I in my capacity as a maintenance Engineer, recently took up a Commercial installation where the local supply co. electrical power is sourced through a CUTOUT which has apart from the standard energymeter and HRC Fuses a TP MCCB also.Now downstream the CUTOUT we have a Main Switchboard comprising again an incomer TP MCCB and outgoing TP and SP MCCBs.Now these outgoing MCCBs feed to individual loads like HVAC chiller, Lighting and Power Distribution boards etc.
Now TP MCCB at CUTOUT and at the Main Switchboard has inbuilt thermal and magnetic releases but no earth fault release.Earth leakage protection is provided only at the load end ie, at the Distribution boards,starter of HVAC Compressor, Switch fuse unit of three phase burner etc - what I mean to say no earth leakage protection at main feed.
Is it o.k. to retain the same design or should I opt for a earth leakage release at either the CUTOUT TP MCCB or the TP MCCB at the Main Switchboard by way of adding a Toroid+ relay+ release combination ??
