27-06-21 Isolator

Isolator:-  Isolator is a off load device, the isolator always works in off load condition. Isolator is a widely used device in transmission & distribution. It is connected with circuit breaker & busbar.

Isolator Symbol

Types of Isolator:- 

1) Center break isolator- 32kv to 220kv

2) Pentograph isolator- 66kv 

3) Knee isolator- 800kv (HVDC, HVAC)

Isolator

Difference Between Isolator & Circuit Breaker:-

Isolator: 

1) Off load device (No load)

2) Never sense fault

3) Manually operated

4) Cost is less

5) It is not use while current flows through the line.

Circuit Breaker:

1) On load device

2) Always sense fault & trip the circuit

3) Automatically operated device

4) Cost is more

5) It is use while current flows through the line.