This preview shows page 1. Sign up to view the full content.
Unformatted text preview: cuits of higher rating, a high-rupturing capacity (H.R.C.) fuse in conjuction with a
switch may serve the purpose of controlling and protecting the circuit. However, such a switchgear
cannot be used profitably on high voltage system (3·3 kV) for two reasons. Firstly, when a fuse
blows, it takes sometime to replace it and consequently there is interruption of service to the customers. Secondly, the fuse cannot successfully interrupt large fault currents that result from the faults on
high voltage system.
With the advancement of power system, lines and other equipments operate at high voltages and
carry large currents. When a short circuit occurs on the system, heavy current flowing through the
equipment may cause considerable damage. In order to interrupt such heavy fault currents, automatic circuit breakers (or simply circuit breakers) are used. A circuit breaker is a switchgear which
can open or close an electrical circuit under both normal and abnormal conditions. Even in instances
where a fuse is adequate, as regards to breaking capacity, a circuit breaker may be preferable. It is...
View Full Document
This note was uploaded on 11/12/2012 for the course MBA 101 taught by Professor Muhannad during the Spring '12 term at Bradford School of Business.
- Spring '12