This presentation provides an introduction to switchgear. It defines switchgear as equipment used for switching, controlling, and protecting electrical circuits and equipment, consisting of devices like switches, fuses, circuit breakers, and relays. Essential features of switchgear include reliability, discrimination between faulty and healthy sections, quick operation, and provisions for manual and instrument control. Common types of switchgear equipment discussed are switches, fuses, circuit breakers, and relays.

1. A
PRESENTATION
OVER
INTRODUCTION
TO
SWITCHGEAR
BY
NIKHIL KACHARE
UNDER THE
GUIDANCE
OF
Mr. NARAYAN PAWAR

2. INTRODUCTION TO
SWITCHGEAR
INDEX
 SWITCHGEAR
 ESSENTIAL FEATURES OF
SWITCHGEAR
 SWITCHGEAR EQUIPMENT

3. SWITCHGEAR
 The apparatus used for switching , controlling &
protecting the electrical circuits & equipments are
known as switchgear.
 The switchgear equipments is essentially used with
switching & interrupting currents either under normal
or abnormal operating condition.
 It consists of devices such as switches , fuses ,
circuit breakers , relays etc.
 Basically every electric circuit needs a switching
device & a protecting device.
 All equipment associated with the fault clearing
process are converted by the term ‘switchgear’.
 Switchgear is an essential part of a power system &
also that of an electric circuit.

4. ESSENTIAL FEATURES OF
SWITCHGEAR
 COMPLETE RELIABILITY
 DISCRIMINATION
 QUICK OPEARATION
 PROVISION FOR MANUAL CONTROL
 PROVISION FOR INSTRUMENTS

5. COMPLETE RELIABILITY
 The ability of the portion system to
operate under the predetermined
conditions is known as reliability.
When fault occur on any power system ,
the switchgear must operate to isolate
the faulty section from remaining circuit.

6. DISCRIMINATION
 When 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 the faulty section from the
system with affecting the healthy
section.

7. QUICK OPEARATION
 When 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 the healthy
parts, thus endangering complete shut
down of the system.

8. PROVISION FOR MANUAL
CONTROL
 A switchgear must have provision for
manual control. In case of electrical
control fails , the necessary operation
can be carried out through manual
control.

9. PROVISION FOR
INSTRUMENTS
 There must be provision for instruments
which may be required. These may be in
the form of ammeter or voltmeter on the
unit itself or the necessary operation
current & voltage transformers for
connecting to the main switch board or a
separate instrument panel.

10. SWITCHGEAR
EQUIPMENT
 Switchgear covers a wide range
equipment with switching and
interrupting currents under both
normal & abnormal conditions.
It includes switches, fuses, circuit breaker,
relays.

11. SWITCHES
 A switch is a device which is used to
open or close an electrical circuit in a
convenient.
The switches are classified are as
follow:-
Air-break switches
oil switches

12. FUSES
 A fuse is a short piece of wire or thin
strip which melts when excessive
current flows through sufficient time.
whenever the current flowing through
fuse element increases beyond its rated
capacity then short circuit or overload
occurs. This raises the temperature and
the fuse element melts, disconnecting
the circuit is protected by it.

13. CIRCUIT BREAKER
 A circuit breaker is an equipment which
can open or close under all condition i.e.
no load, full load & fault condition.
It is designed that it can be operated
manually under normal condition &
automatically under abnormal condition.

14. RELAYS
 A relay is a device which detects the
faults & supplies information to the
circuit breaker for circuit interruption.