Components of a Switchgear
- Circuit Breakers
- Fuses & MCBs
- Voltage and current transformers
- Protective relays
- Measuring instruments
- Busbars , insulators & other small parts
- Metal enclosure
Types of Circuit Breakers
- Air Circuit Breakers
**Main Incoming & Outgoing ACBs
**Moulded case circuit breakers (MCCBs)
**Miniature circuit breakers (MCBs)
- Oil Circuit Breaker
- Vacuum Circuit Breaker
- SF6 (Hexafluoride) Circuit Breaker
Ring main distribution system
- Oil or SF6 RMU
- Relative simple and economical
- Consist of circuit breaker or fuse taps with load-break isolator on either side
Function of a Circuit Breaker
- To isolate or connect the equipment or power supply from/to the power source
- To ensure the unimpeded flow of current in the network under normal operating conditions
- To interrupt the flow of excessive current in a faulty network through the protective relays
- Maintenance should be carried out every 2,000 operations or once a year whichever occurs first