Switchgear

M. Nageswar Rao, Sr.Mgr.(EMD)

Date: 03.10.2015

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Presentation LayoutMotor applications Induction Motors

Starting methodsSpeed control methods

Synchronous MotorsStarting methodsSpeed control methods

DC MotorsStarting methodsSpeed control methods

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SwitchgearSwitch

Electrical device used to open/close current path in an electrical ckt.

SwitchgearCombination of switching devices with

associated eqpt. of Control Measuring Protection

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SwitchgearFunctions

Carrying normal load currentMaking/ breaking normal load currentClearing the fault current

Parts of swgr.Switching devicesPower ckt.Control ckt.

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Switchgear devicesProtection devices

Circuit breakersMCCBRelaysFuse

Isolating devicesIsolator/ Earth switch, MCB, SFU

MeasuringCT, PTAmmeter, Voltmeter, Energy meter

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Switchgear classificationBy voltage class

LV, MV, HV, EHVOutdoor

VCB, ABCB, SF6Indoor

Vaccuum contactor, ACBMetal enclosure, Metal clad

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Metal clad vs Metal enclosureMetal Enclosed swgr. Metal Clad swgr:switchgear is assembled

inside standard metal enclosures.

Different chambers are made like breaker chamber, bus bar chamber, LT Chamber, Cable chamber etc

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CB & Relay

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Circuit Breaker

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MCCB

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RelayNumerical Relay,Overload Relay,Coupling Relay

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Isolating devicesIsolator, SFU, MCB

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Thank you all