ESSENTIAL FEATURES OF SWITCHGEAR

Table of Contents

The essential features of switchgear are:

(I) COMPLETE RELIABILITY

With the continued trend of interconnection and the increasing capacity of generating stations, the need for reliable switchgear has become of paramount importance. This is not surprising because switchgear is added to the power system to improve reliability. When a fault occurs on any part of the power system, the switchgear must operate to isolate the faulty section from the remaining circuit.

(II) ABSOLUTELY CERTAIN DISCRIMINATION

When a fault occurs on any section of the power system, the switchgear must be able to discriminate between the faulty section and the healthy section. It should isolate the faulty section from the system without affecting the healthy section. This will ensure continuity of supply.

(III) QUICK OPERATION

When a fault occurs on any part of the power system, the switchgear must operate quickly so that no damage is done to generators, transformers, and other equipment by the short-circuit currents. If the fault is not cleared by the switchgear quickly, it is likely to spread into healthy parts, thus endangering the complete shutdown of the system.

(IV) PROVISION FOR MANUAL CONTROL

A switchgear must have a provision for manual control. In case the electrical (or electronics) control fails, the necessary operation can be carried out through manual control.

(V) PROVISION FOR INSTRUMENTS

There must be provision for instruments that may be required. These may be in the form of an ammeter or voltmeter on the unit itself or the necessary current and voltage transformers for connecting to the main switchboard or a separate instrument panel.

ESSENTIAL FEATURES OF SWITCHGEAR | Switchgear: Features, Components, and Classification