Definition – An Isolator is a device which is used to switch off or switch ON power supply. It’s an Off load device because there no arc quenching techniques provided in it, it operates manually, it doesn’t provide any protection. It looks like an MCB for LT applications.
(Note– For high voltage applications, these isolators work as a secondary protection which is placed after the Circuit Breaker. Isolators are switched off after main supply is off and switched ON before the main supply is ON.)
It is available for single & three phase load. They are available in DP, TP & 4P forms. Current ranges are given below for 415V applications –
DP Isolator – 32A, 40A, 63A, 100, 125A.
TP Isolator – 32A, 40A, 63A, 100, 125A.
4P Isolator- 32A, 40A, 63A, 100, 125A.