1Module One04/11/23
SUBSTATION COMMISSIONING COURSE
MODULE ONE
MEDIUM VOLTAGESWITCHGEARASSEMBLIES
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INTRODUCTION
• The electrical commissioning and acceptance testing of electric power systems is essential for the energization of any electrical system for the first time.
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INTRODUCTION
Module One• Introduce the applicable switchgear
standards used in North America• Describe the construction aspects of
switchgear assemblies• Indentify NETA testing requirements• Perform acceptance testing
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INTRODUCTION
Skills from module one:• Know the major and basic parts of
switchgear assemblies• Use NETA switchgear testing section• Perform acceptance testing
procedures
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SWITCHGEAR STANDARDS
CANADIAN STANDARDS
• CSA Canadian Standards Association
• EEMAC Electrical Equipment Manufacturers Association of Canada
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SWITCHGEAR STANDARDS
NORTH AMERICAN STANDARDS
• ANSI American National Standards Institute
• IEEE Institute of Electrical and Electronics Engineers
• NEMA National Electrical Manufacturers Association
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SWITCHGEAR STANDARDS
INTERNATIONAL STANDARDS
• IEC International Electrotechnical Commission
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SWITCHGEAR STANDARDS
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SWITCHGEAR STANDARDS
Canadian Standard:• CSA standard
– CSA Standard C22.2 No. 31 – 2010
– Switchgear Assemblies
– Ninth edition
• Devices included:– switches;– interrupting devices;– air circuit breakers;– power circuit breakers;
and– control, metering,
protective, and regulating equipment with associated interconnections and supporting structures.
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SWITCHGEAR STANDARDS
Canadian Standard:• CSA standard
– CSA Standard C22.2 No. 31 – 2010
– Switchgear Assemblies
– Ninth edition
• Standard covers:– Covers construction
and design features– Nominal voltage of
46Kv or less– Components within the
assemblies must comply with CEC requirements
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SWITCHGEAR STANDARDS
CEC Approved Labels
• CSA• UL-C• Special Inspection
sticker
• CSA label– CSA sticker or CSA
logo on the nameplate– CSA designation
obtained by application, inspection and testing
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SWITCHGEAR STANDARDS
CEC Approved Labels
• CSA• UL-C• Special Inspection
sticker
• UL-C label– Equipment made in
USA– Tested by
Underwriters Laboratories to CSA standards
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SWITCHGEAR STANDARDS
CEC Approved Labels
• CSA• UL-C• Special Inspection
sticker
• Special Inspection Sticker– Requires special
inspection by the electrical inspector
– Requires document review
– Sticker affixed, dated and signed by the electrical inspector
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SWITCHGEAR STANDARDS
US Standards• IEEE C37.20.1 • IEEE C37.20.2 • IEEE C37.20.3• IEEE C37.20.4
• IEEE C37.20.1– Standard for Metal-
Enclosed Low-Voltage Power Circuit Breaker Switchgear
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SWITCHGEAR STANDARDS
US Standards• IEEE C37.20.1 • IEEE C37.20.2 • IEEE C37.20.3• IEEE C37.20.4
• IEEE C37.20.2– Standard for Metal-
Clad Switchgear
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SWITCHGEAR STANDARDS
US Standards• IEEE C37.20.1 • IEEE C37.20.2 • IEEE C37.20.3• IEEE C37.20.4
• IEEE C37.20.3– Standard for Metal-
Enclosed Interrupter Switchgear
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SWITCHGEAR STANDARDS
US Standards• IEEE C37.20.1 • IEEE C37.20.2 • IEEE C37.20.3• IEEE C37.20.4
• IEEE C37.20.4– Standard for Indoor
AC Switches (1kV – 38 kV) for Use in Metal Enclosed Switchgear
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SWITCHGEAR STANDARDS
IEC Standards• IEC Standard
62271-200
• IEC 62271-200– AC metal-enclosed
switchgear and controlgear for rated voltage above 1kV and up to and including 52kV
Note:
Comparable to the ANSI / IEEE Standard C37.20.2.
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SWITCHGEAR
What is Medium Voltage ?• ANSI/IEEE 1585-2002: (1 - 35 kV)• IEEE Std 1623-2004: (1 -35 kV • NECA/NEMA 600-2003: (.6 – 69 kV)• Littlefuse: (2.4 -38 Kv)
• Siemens: (1 – 38 kV) 600 volts to 69,000
Note: No true definition
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SWITCHGEAR
What is a MV Switchgear ?• Compartmentalized assemblies of
switching and interrupting devices • Operating from 1000V to 38 kV • Supplied from an insulated main bus
structure, along with control,
metering, protective and regulating equipment with associated
interconnections and supporting structure.
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SWITCHGEAR
Major Parts• Control devices• Switching and
Interrupting devices• Metering devices• Protective devices• Regulating devices• Interconnections• Supporting structure
Control Devices• Local controls
– Trip/close controls– Trip/close HMI
• Remote controls– Trip/close Interface -
Interpose– Trip/close RTU
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SWITCHGEAR
Major Parts• Control devices• Switching and
Interrupting devices• Metering devices• Protective devices• Regulating devices• Interconnections• Supporting structure
Switching & Interrupting devices
• Circuit breakers– Vacuum– SF6– Air-magnetic
• Switches– Load break– Isolation
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SWITCHGEAR
Major Parts• Control devices• Switching and
Interrupting devices• Metering devices• Protective devices• Regulating devices• Interconnections• Supporting structure
Metering Devices• CT’s and VT’s (PT’s)• Switchboard Instruments
– Volts, amps, watts, vars, PF, Hz
• Transducers• Revenue Metering
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SWITCHGEAR
Major Parts• Control devices• Switching and
Interrupting devices• Metering devices• Protective devices• Regulating devices• Interconnections• Supporting structure
Protective Devices• Discrete Protective Relays• Digital Relays• Overload relays
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SWITCHGEAR
Major Parts• Control devices• Switching and
Interrupting devices• Metering devices• Protective devices• Regulating devices• Interconnections• Supporting structure
Regulating Devices• Temperature controller• Voltage regulator function
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SWITCHGEAR
Major Parts• Control devices• Switching and
Interrupting devices• Metering devices• Protective devices• Regulating devices• Interconnections• Supporting structure
Interconnections• Bus-bar assemblies
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SWITCHGEAR
Major Parts• Control devices• Switching and
Interrupting devices• Metering devices• Protective devices• Regulating devices• Interconnections• Supporting structure
Supporting structures• Designed for structural
integrity• Support weight on
equipment• Withstand forces of
operating equipment• Seismic options• Arc flash option
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SWITCHGEAR
5 Vertical Section Unit 3 Vertical Section Unit
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SWITCHGEAR
Characteristics:• Voltage category• Current rating• Mechanical aspects• Metal-clad Vs Metal-
enclosed
Voltage category• 5 kV• 15 kV• 27 kV• 38 kV
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SWITCHGEAR
Characteristics:• Voltage category• Current rating• Mechanical aspects• Metal-clad Vs Metal-
enclosed
Current Rating• 1200A, 2000A, 3000A• Fan cooled for above
3000A
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SWITCHGEAR
Characteristics:• Voltage category• Current rating• Mechanical aspects• Metal-clad Vs Metal-
enclosed
Mechanical Aspects• Removable / drawout
circuit breakers• Insulated Main Bus
section• In / out sections• Compartmentalized• Metal barriers for vertical
structures and compartments
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SWITCHGEAR
Metal Enclosed Vs Metalclad
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SWITCHGEARApplication
example
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SWITCHGEAR
Basic Parts• Vertical Structure• Compartments
Vertical Structure• Width: 26”, 36” or 42”• Height: 90 to 100”• Structures are bolted together
to form continuous assy.• Front are hinged doors• Rear are removable plate or
hinged (optional)
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SWITCHGEAR
Basic Parts• Vertical Structure• Compartments
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SWITCHGEAR
Basic Parts• Vertical Structure• Compartments
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SWITCHGEAR
Basic Parts• Vertical Structure• Compartments
Compartments• Circuit Breakers• Main Bus• Cable Connection / Line• Low Voltage / Control• PT / Auxiliary
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SWITCHGEAR
Basic Parts• Compartments
A - Circuit Breakers
B - Main Bus
C - Cable / Line
D - Low Voltage / Control
E - PT / Auxiliary
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SWITCHGEAR
Basic Parts• CB compartment
- Enclosure
Enclosure• Top, bottom, left / right, rear• Faceplate is the front when CB
is fully racked in– The current carrying parts
are compartmentalized– Provides pri and sec
connections points• Mechanical Interlocks• Testing in the test /disconnect
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SWITCHGEAR
Basic Parts• CB compartment
- Enclosure
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SWITCHGEAR
Basic Parts• CB compartment
- Primary Electrical Connections
Primary Electrical Connections• 6 primary connecting device
– 2 per phase, line and load side
– Pressured finger clusters– Mate with stationary bus
bar connecting stabs
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SWITCHGEAR
Basic Parts• CB compartment
- Primary Electrical Connections
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SWITCHGEAR
Basic Parts• CB compartment
- Primary Electrical Connections
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SWITCHGEAR
Basic Parts• CB compartment
- Secondary Electrical Connections
Secondary Elect. Connections• Male to female contact plugs• Complete circuits for controls• Auto Engaged in
CONNECTED pos’n• Auto Dis-engaged is
DISCONNECTED pos’n• Manually engaged in TEST
pos’n
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SWITCHGEAR
Basic Parts• CB compartment
– Secondary Electrical Connections
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SWITCHGEAR
Basic Parts• CB compartment
– Secondary Electrical Connections
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SWITCHGEAR
Basic Parts• CB compartment
- Safety Interlocks
Safety Interlocks• Required by governing
standards• Incorporates mechanical and
electrical interlocks
Note:
DO NOT bypass or defeat the interlocks, they are necessary for the safe operation of the circuit breaker
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SWITCHGEAR
Basic Parts• CB compartment
- Extension
Rails
Extension Rails• Provide support• Allows equipment to be
withdrawn from the compartment
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SWITCHGEAR
Basic Parts• CB compartment
- Extension
Rails
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SWITCHGEAR
Basic Parts• Main Bus
Compartment
Main Bus Compartment• Houses the main bus• Buses are mounted on
insulators• Breakers connects to the main
bus via bus joints• Isolating barriers in each
vertical structure compartmentalize the main bus
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SWITCHGEAR
Basic Parts• Main Bus
Compartment1. Circuit Breaker
Compt2. Main Bus Compt3. Bus Bars4. CB to Bus Bar
Conn5. Primary Conn6. Cable Compt
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SWITCHGEAR
Basic Parts• Main Bus
Compartment
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SWITCHGEAR
Basic Parts• Main Bus
Compartment
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SWITCHGEAR
Basic Parts• Main Bus
Main Bus • Extends the length of the
assembly (typical)• Pass through insulated
opening on sides of structures• Bus are not one continuous
piece• Supported and braced• Vertical sections are
compartmentalized• Silver plate bus joints
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SWITCHGEAR
Basic Parts• Main Bus Ratings
Main Bus Ratings• 1200A, 2000A or 3000A• + 3000A using forced air
cooling (fans via thermostat)• Design for temperature rise
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SWITCHGEAR
Basic Parts• Line Compartment
Line Compartment• Rear most compartment• Bolted rear panel access• Rear doors are optional• Cable or bus duct entry area• Top or bottom entry• Also used for surge arresters
or control power transformers• Run length of vertical structure
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SWITCHGEAR
Basic Parts• Line
Compartment
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SWITCHGEAR
Basic Parts• Line
Compartment
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SWITCHGEAR
Basic Parts• Control
Compartment
Control Compartment• The space available between
the breaker faceplate and the front door.
• Used for mounting control devices, relays and metering
• Limited space availability• Items can be mounted on the
rear door panel or inserted in the door panel
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SWITCHGEAR
Basic Parts• Control
Compartment
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SWITCHGEAR
Basic Parts• Auxiliary
Compartment
Auxilliary Compartment• Located above or below a
breaker compartment (typical)• Can be an entire vertical
section• Often used for PT’s or CPT’s
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SWITCHGEAR
Basic Parts• Auxiliary
Compartment
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SWITCHGEAR
Basic Parts• Auxiliary
Compartment1. Drawout PT’s2. Drawout CPT’s3. Drawout Fuses4. Fixed CPT
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SWITCHGEAR
Installations• Indoor• Outdoor
Indoor• Classification based on
enclossure type– Nema 1, 1A, 2, 3R, 12
• Classification based of function– Arc resistant, seismic rated,
weatherproof, dust proof, drip proof, sprinkler proof
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SWITCHGEAR
Installations• Indoor• Outdoor
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SWITCHGEAR
Installations• Indoor• Outdoor
– Aisle-less– Sheltered Aisle– Common Aisle
Outdoor• Aisle-less switchgear
– Weatherproof, gasketed doors / rear panels / doors
– Heaters minimize condensation and moisture
– NEMA 3, 3R, 4 or 4X
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SWITCHGEAR
Installations• Outdoor
– Aisle-less– Sheltered
Aisle– Common Aisle
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SWITCHGEAR
Installations• Indoor• Outdoor
– Aisle-less– Sheltered Aisle– Common Aisle
Outdoor• Sheltered Aisle Switchgear
– Aisle is part of the enclosure and provided at the front
– Weatherproof gasketed door at both ends of the
– Nema 3R enclosure
– Heaters minimize condensation and moisture
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SWITCHGEAR
Installations• Outdoor
– Aisle-less– Sheltered
Aisle– Common Aisle
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SWITCHGEAR
Installations• Indoor• Outdoor
– Aisle-less– Sheltered Aisle– Common Aisle
Outdoor
Common Aisle Switchgear– As per Sheltered Aisle with
switchgear on both sides of the aisle
– Installed in 2 parts
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SWITCHGEAR
Installations• Outdoor
– Aisle-less– Sheltered
Aisle– Common Aisle
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SWITCHGEAR
Testing• Type of testing varies
upon what standards it was designed to– CSA, EEMAC– ANSI, IEEE, NEMA– IEC
Type of Tests• Design and proof test• Production test
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SWITCHGEAR STANDARDS
• Built and tested to a specific set of engineering standards
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SWITCHGEAR
Type of Testing• Design and Proof• Production
Design and Proof Testing• Short circuit testing • BIL testing • Dielectric testing • Continuous current testing • Mechanical life testing • Thermal testing • Environmental testing
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SWITCHGEAR
Type of Testing• Design and Proof• Production tests
– Circuit breaker– Assembled
equipment
Circuit Breaker Testing• Verification of nameplate
ratings • Control wiring check • Control wiring insulation test • Charging motor insulation test • Operation of switches, control
devices, latches and interlocks
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SWITCHGEAR
Type of Testing• Design and Proof• Production tests
– Circuit breaker– Assembled
equipment
Circuit Breaker Testing• Breaker operation at minimum,
maximum, and rated control voltages
• Vacuum interrupter operation and withstand tests
• Breaker contact resistance • Closing and opening timing
tests • Dielectric tests
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SWITCHGEAR
Type of Testing• Design and Proof• Production tests
– Circuit breaker– Assembled
equipment
Assembled Equipment Testing• Component nameplate
verification for compatible application
• Dielectric tests • Mechanical testing of all
operational parts and devices • Control wiring continuity
verification
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SWITCHGEAR
Type of Testing• Design and Proof• Production tests
– Circuit breaker– Assembled
equipment
Assembled Equipment Testing• Operation of all relays,
instruments, meters and other devices
• Control wiring insulation tests • Instrument transformer polarity
verification tests • Sequence of operation tests, if
applicable