Most of the protection relays consist of some arrangement of electromagnets with armature or induction disc, which carry contacts. The relays also carry the closing or opening of contacts control devices like trip coils of the ci…
Induction relay is a type of electromagnetic relay, that works on the principle of electromagnetic induction and it resembles a split-phase induction motor. The operating force developed will be due to the interactions of fluxes …
A protective relay that operates when the current flowing in the circuit reaches a predetermined value is called Overcurrent Relay. The predetermined value of the current at which the relay starts operating by initiating a trip s…
These relays can operate for power flow in a specified direction. Directional power relay operates on the same principle as that of induction type watt-hour relay. The difference is that in the case of an induction type watt-hour…
An overcurrent relay will operate for fault current flow in any direction, i.e., either in forward or in the reverse direction. In order to achieve the operation of the relay in the forward direction, a directional feature is add…
The air blast circuit breaker is the type of circuit breaker where high pressure (at a pressure of 30 kg/cm 2 ) air-blast is used for arc extinction. So they seek applications in the high voltage (132 kV and above) transmission s…
The minimum oil circuit breaker is also called a small or poor oil circuit breaker. It required a small percentage of oil (about 10% of oil) used in the case of the bulk oil circuit breaker. The oil is mainly used for the arc ex…
