GE SecoGear User guide

DET-882 Application and Technical Guide
SecoGear
$ZE $ZE8444MecP[-R[PS Switchgear
GE Energy Connections
Industrial Solutions

©2016 General Electric All Rights Reserved i
HAZARD CLASSIFICATIONS
The following important highlighted information appears
throughout this document to warn of potential hazards or
to call attention to information that clarifies a procedure.
Carefully read all instructions and become familiar with the
devices before trying to install, operate, service or maintain
this equipment.
DANGER
Indicates a hazardous situation that, if not avoided, will
result in death or serious injury.
WARNING
Indicates a hazardous situation that, if not avoided, could
result in death or serious injury.
CAUTION
Indicates that if the hazard is not avoidedcould result in
minor or moderate injury.
NOTICE
Is used to notify of practices not related to personal injury.
TRADEMARKS
SecoGear® Seco RMU®
Seco Cube® SecoBloc®
SecoVac® VB2+ Multilin®
All third party trademarks are the property of their
respective owners.
WARRANTY
This document is based on information available at the
time of its publication. While efforts have been made to
ensure accuracy, the information contained herein does
not cover all details or variations in hardware and software,
nor does it provide for every possible contingency in
connection with installation, operation, and maintenance.
Features may be described herein that are not present in
all hardware and software systems.
GE Industrial Solutions assumes no obligation of notice to
holders of this document with respect to changes
subsequently made. GE Industrial Solutions makes no
representation or warranty, expressed, implied, or
statutory, with respect to, and assumes no responsibility
for the accuracy, completeness, sufficiency, or usefulness
of the information contained herein.
No warrantees of merchantability or fitness for purpose
shall apply.
Contact your local sales office if further information is
required concerning any aspect of SecoGear switchgear
and SecoVac VB2+ breaker operation or maintenance.

SecoGear Medium-voltage Switchgear Application and Technical Guide DET-882
ii ©2017 General Electric All Rights Reserved
TABLE OF CONTENTS
SECTION 1. SecoGear Switchgear Concepts and Basic Configurations......................................................................................1
SecoGear Metal-clad Switchgear...............................................................................................................................................................................................1
Switchgear Standards......................................................................................................................................................................................................................3
Underwriters Laboratories, Inc. (UL)....................................................................................................................................................................................3
Service Conditions........................................................................................................................................................................................................................3
Temperature................................................................................................................................................................................................................................3
Humidity........................................................................................................................................................................................................................................3
Altitude...........................................................................................................................................................................................................................................3
Applicable Industry Standards...............................................................................................................................................................................................3
Modular Construction and Typical Sectional Views.........................................................................................................................................................3
Modular Compartments............................................................................................................................................................................................................3
Rollout Configurations................................................................................................................................................................................................................5
Two-High Breaker and Auxiliary Stacking.......................................................................................................................................................................6
SECTION 2. Circuit Breaker Selection.............................................................................................................................................. 10
Circuit Breaker Ratings..................................................................................................................................................................................................................10
Selection Considerations..............................................................................................................................................................................................................10
Circuit Voltage..............................................................................................................................................................................................................................10
System Frequency ....................................................................................................................................................................................................................10
Short-Circuit Current................................................................................................................................................................................................................10
Closing and Latching Current..............................................................................................................................................................................................11
Continuous Current...................................................................................................................................................................................................................11
Rated Interrupting Time..........................................................................................................................................................................................................11
Duty Cycle......................................................................................................................................................................................................................................11
Special Switching Applications.................................................................................................................................................................................................11
Automatic Transfer...................................................................................................................................................................................................................11
Capacitor Switching..................................................................................................................................................................................................................12
Service Conditions...........................................................................................................................................................................................................................12
Usual Service Conditions........................................................................................................................................................................................................12
Unusual Service Conditions..................................................................................................................................................................................................12
Abnormal Temperature......................................................................................................................................................................................................12
Temperature Rise...................................................................................................................................................................................................................12
High Altitude.............................................................................................................................................................................................................................12
Breaker Accessories .......................................................................................................................................................................................................................13
Breaker Lift Truck.............................................................................................................................................................................................................................13
Related Circuit Breaker References........................................................................................................................................................................................14
Typical Breaker Device Internals.............................................................................................................................................................................................16
SECTION 3. Control Power Equipment............................................................................................................................................ 18
Control Power Requirements.....................................................................................................................................................................................................18
Breaker Close and Trip Considerations..........................................................................................................................................................................18
Breaker Tripping .........................................................................................................................................................................................................................18
DC Battery Trip........................................................................................................................................................................................................................19
SecoVac Autocharge Capacitor Trip Device............................................................................................................................................................19
Direct Acting Undervoltage Trip Device.....................................................................................................................................................................19
Breaker Closing...........................................................................................................................................................................................................................19
Indicating Lamps........................................................................................................................................................................................................................20
Relaying................................................................................................................................................................................................................................................20
Excitation Power...............................................................................................................................................................................................................................20
Other Loads.........................................................................................................................................................................................................................................20
Control Power Source Selection...............................................................................................................................................................................................21
DC Control Power Equipment..............................................................................................................................................................................................21
Battery Systems.........................................................................................................................................................................................................................21
Lead-Acid Batteries..............................................................................................................................................................................................................21
Nickel-Cadmium Batteries................................................................................................................................................................................................21

DET-882 SecoGear Medium-voltage Switchgear Application and Technical Guide
©2017 General Electric All Rights Reserved iii
Battery Capacity and Sizing.................................................................................................................................................................................................21
Battery Chargers.........................................................................................................................................................................................................................22
AC Control Power Equipment.....................................................................................................................................................................................................23
Application......................................................................................................................................................................................................................................23
Selection..........................................................................................................................................................................................................................................23
Guide to Estimating Heat Loss...................................................................................................................................................................................................24
SECTION 4. System and Equipment Protection.............................................................................................................................25
Basic System Protection...............................................................................................................................................................................................................28
Phase Overcurrent Protection..............................................................................................................................................................................................28
Incoming Lines.........................................................................................................................................................................................................................28
Feeders........................................................................................................................................................................................................................................28
Feeder Ties.................................................................................................................................................................................................................................28
Bus Ties........................................................................................................................................................................................................................................28
Transformers............................................................................................................................................................................................................................28
Generators.................................................................................................................................................................................................................................28
Ground Overcurrent Protection..........................................................................................................................................................................................29
Incoming Lines.........................................................................................................................................................................................................................29
Feeders........................................................................................................................................................................................................................................29
Transformers and Generators.........................................................................................................................................................................................30
Directional Phase Overcurrent Protection.....................................................................................................................................................................30
Directional Ground Overcurrent Protection..................................................................................................................................................................30
High Impedance Ground Fault Detection......................................................................................................................................................................30
Differential Protection..............................................................................................................................................................................................................30
Bus Protection..........................................................................................................................................................................................................................31
Transformer Protection.......................................................................................................................................................................................................31
Motors...........................................................................................................................................................................................................................................31
Transmission Line...................................................................................................................................................................................................................31
Generators.................................................................................................................................................................................................................................31
Open Phase Protection............................................................................................................................................................................................................31
Automatic Reclosing.................................................................................................................................................................................................................31
Directional Power, Underfrequency, and Undervoltage Protection................................................................................................................32
Arc Flash Detection..........................................................................................................................................................................................................................32
Basic Equipment Protection........................................................................................................................................................................................................32
Circuit Breaker Control and Control Power Protection...........................................................................................................................................32
Instrumentation, Current, and Voltage Transformers.............................................................................................................................................33
AM and VM Scales..................................................................................................................................................................................................................33
CT and VT Ratios.....................................................................................................................................................................................................................33
Metering and Test Block..........................................................................................................................................................................................................34
Control and Transfer Switches........................................................................................................................................................................................34
Surge Protection..........................................................................................................................................................................................................................34
ANSI Device Functions and Acronyms..................................................................................................................................................................................34
SECTION 5. SecoGear Switchgear Applications.............................................................................................................................37
Glossary: Basic Equipment Applications..............................................................................................................................................................................37
General-Purpose Feeders (GPF)................................................................................................................................................................................................38
Protective Scheme Selection................................................................................................................................................................................................38
Optional Equipment Selection..............................................................................................................................................................................................38
Protection...................................................................................................................................................................................................................................38
Current Transformers for Differential Circuits.........................................................................................................................................................38
Indication....................................................................................................................................................................................................................................38
Control..........................................................................................................................................................................................................................................39
Transformer Primary Feeders (TPF).........................................................................................................................................................................................40
Protective Scheme Selection................................................................................................................................................................................................40
Optional Equipment Selection..............................................................................................................................................................................................40
Single-Source Incoming Lines (SSIL), or Dual Source with Normally Open Tie Breakers............................................................................40

SecoGear Medium-voltage Switchgear Application and Technical Guide DET-882
iv ©2017 General Electric All Rights Reserved
Protective Scheme Selection................................................................................................................................................................................................40
Optional Equipment Selection.............................................................................................................................................................................................41
Protection...................................................................................................................................................................................................................................41
Indication...................................................................................................................................................................................................................................41
Control.........................................................................................................................................................................................................................................42
Dual-Source Incoming Lines (DSIL).........................................................................................................................................................................................43
Basic Equipment Selection....................................................................................................................................................................................................43
Optional Equipment Selection.............................................................................................................................................................................................43
Protection...................................................................................................................................................................................................................................43
Indication...................................................................................................................................................................................................................................43
Control.........................................................................................................................................................................................................................................43
Location of Optional Devices...........................................................................................................................................................................................43
Bus Ties (BT).........................................................................................................................................................................................................................................44
Basic Equipment Selection....................................................................................................................................................................................................44
Optional Equipment Selection.............................................................................................................................................................................................44
Protection...................................................................................................................................................................................................................................44
Indication...................................................................................................................................................................................................................................45
Control.........................................................................................................................................................................................................................................45
Bus Entrances (BE)...........................................................................................................................................................................................................................46
Basic Equipment Selection....................................................................................................................................................................................................46
Optional Indication Selection...............................................................................................................................................................................................46
Induction Motor Feeders (IMF)...................................................................................................................................................................................................46
Protective Scheme Selection................................................................................................................................................................................................46
Optional Equipment Selection (for IMFE, IMF1, IMF2)..............................................................................................................................................47
Protection...................................................................................................................................................................................................................................47
Indication...................................................................................................................................................................................................................................47
Control.........................................................................................................................................................................................................................................47
Location of Optional Devices...........................................................................................................................................................................................47
Reduced Voltage Starting............................................................................................................................................................................................................49
Synchronous Motor Feeders (SMF).........................................................................................................................................................................................49
Protective Scheme Selection................................................................................................................................................................................................49
Optional Equipment Selection (for SMF1 and SMF2)...............................................................................................................................................50
Protection...................................................................................................................................................................................................................................50
Excitation....................................................................................................................................................................................................................................50
Indication...................................................................................................................................................................................................................................50
Control.........................................................................................................................................................................................................................................50
Location of Optional Devices...........................................................................................................................................................................................50
Standard Breaker and Auxiliary Configurations..............................................................................................................................................................52
Standard Tie Breaker and Auxiliary Configurations......................................................................................................................................................53
SECTION 6. Standard SecoGear Construction, Features, and Installation.............................................................................. 55
Documentation.................................................................................................................................................................................................................................55
Construction.......................................................................................................................................................................................................................................55
Indoor Equipment......................................................................................................................................................................................................................55
Hardware........................................................................................................................................................................................................................................55
Breaker Compartments..........................................................................................................................................................................................................55
Visual Breaker Position Indication................................................................................................................................................................................56
Auxiliary Compartments........................................................................................................................................................................................................56
Compartment Doors............................................................................................................................................................................................................56
Safety Interlocks.........................................................................................................................................................................................................................57
Secondary Disconnect Interlocking.............................................................................................................................................................................57
Safety Key Lock Provisions...............................................................................................................................................................................................58
Padlock for Open/Close Pushbutton (Optional).....................................................................................................................................................59
Main Bus.........................................................................................................................................................................................................................................59
Secondary Control.....................................................................................................................................................................................................................59
Door-mounted Devices......................................................................................................................................................................................................59
Equipment-mounted Devices.........................................................................................................................................................................................59

DET-882 SecoGear Medium-voltage Switchgear Application and Technical Guide
©2017 General Electric All Rights Reserved v
Wiring............................................................................................................................................................................................................................................60
Power Termination Compartment.....................................................................................................................................................................................60
Ground Bus....................................................................................................................................................................................................................................61
Equipment Heaters....................................................................................................................................................................................................................61
Finish and Paint...........................................................................................................................................................................................................................61
Unit Nameplates.........................................................................................................................................................................................................................61
Accessories....................................................................................................................................................................................................................................61
Breaker Test Box.....................................................................................................................................................................................................................61
Breaker Racking Mechanism...........................................................................................................................................................................................61
Ground and Test Device.....................................................................................................................................................................................................61
Identification of Breakers and Equipment.....................................................................................................................................................................62
Installation Information.................................................................................................................................................................................................................63
Shipping Splits..............................................................................................................................................................................................................................63
Indoor Foundation Preparation...........................................................................................................................................................................................63
Anchoring Details........................................................................................................................................................................................................................64
Embedded Floor Channel Requirements...................................................................................................................................................................64
SECTION 7. Ground and Test Device ...............................................................................................................................................66
Safety......................................................................................................................................................................................................................................................66
TABLE OF FIGURES
Figure 1-1: Typical SecoGear 2-High Section............................................................................................................................................................................1
Figure 1-2: Section Contents...............................................................................................................................................................................................................2
Figure 1-3: Typical One-High Breaker............................................................................................................................................................................................2
Figure 1-4: Typical Two-High Breakers.........................................................................................................................................................................................3
Figure 1-5: Dual VT Rollouts, Line/Bus Connected – Upper or Lower Section..........................................................................................................4
Figure 1-6: Dual CPT Rollouts, Line/Bus Connected – Upper or Lower Section.......................................................................................................4
Figure 1-7: 1200 A/2000 A – Upper or Lower Breaker Section.........................................................................................................................................4
Figure 1-8: VT Rollout, Line/Bus Connected and Fuse Rollout, Line Connected – Lower Section..................................................................4
Figure 1-9: Dual Rollouts.......................................................................................................................................................................................................................5
Figure 1-10: Single Rollouts.................................................................................................................................................................................................................5
Figure 1-11: Breaker in Compartment A, Bus-connected VTs in Compartment B.................................................................................................6
Figure 1-12: Breaker in Compartment A, Line-connected VTs in Compartment B................................................................................................6
Figure 1-13: Breaker in Compartment A, Bus-connected VTs and CPT Fuse Rollout in Compartment B..................................................6
Figure 1-14: Breaker in Compartment A, Line-connected CPT and VT Rollouts in Compartment B.............................................................6
Figure 1-15: Breaker in Compartment A, Line- and Bus-connected VT Rollouts in Compartment B...........................................................7
Figure 1-16: Breaker in Compartment B, Bus-connected VT Rollout in Compartment A...................................................................................7
Figure 1-17: Breaker in Compartment B, Bus-connected CPT in Compartment A.................................................................................................7
Figure 1-18: Bus Entry in Compartment A – Cabling Above, Breaker in Compartment B – Cabling Below..............................................7
Figure 1-19: Breaker in Compartment B, Bus-connected VTs and CPT in Compartment A..............................................................................8
Figure 1-20: Breaker in Compartment B, Line-connected VT Rollouts in Compartment A................................................................................8
Figure 1-21: Typical Two-high Breaker Section – Cabling Below....................................................................................................................................8
Figure 1-22: Typical Two-high Breaker Section – Cabling Above...................................................................................................................................8
Figure 1-23: Breaker in Compartment A – Cabling Above, Bus Entry in Compartment B – Cabling Below..............................................9
Figure 1-24: Breaker in Compartment A, Bus-connected VTs and Line-connected Fuse Rollout in Compartment B........................9
Figure 1-25: Bus-connected VTs in Compartment A, Bus Tie Breaker in Compartment B................................................................................9
Figure 1-26: Bus-connected VTs in Compartment A, Aux Tie in Compartment B..................................................................................................9
Figure 2-1: SecoVac VB2+ Circuit Breaker................................................................................................................................................................................10
Figure 2-2: Lift Truck.............................................................................................................................................................................................................................14
Figure 2-3: SecoVac VB2+ Breaker Front Panel.....................................................................................................................................................................15
Figure 2-4: Spring Discharge Instructions................................................................................................................................................................................15
Figure 2-5: System Wiring Diagram.............................................................................................................................................................................................16
Figure 2-6: Terminal Block Located in Switchgear...............................................................................................................................................................16
Figure 2-7: Secondary Disconnect...............................................................................................................................................................................................16
Figure 2-8: Example – Main Breaker Control Circuit, 850 Relay, Expanded MOC Switch................................................................................17
Figure 4-1: Multilin Website Features – Motor Protection Selection...........................................................................................................................26

SecoGear Medium-voltage Switchgear Application and Technical Guide DET-882
vi ©2017 General Electric All Rights Reserved
Figure 4-2: Multilin Website Features – Digital Metering Selection............................................................................................................................27
Figure 5-1: General-Purpose Feeder...........................................................................................................................................................................................39
Figure 5-2: Transformer Primary Feeder..................................................................................................................................................................................40
Figure 5-3: Single-source Incoming Line..................................................................................................................................................................................42
Figure 5-4: Dual-Source Incoming Line.....................................................................................................................................................................................44
Figure 5-5: Bus Tie.................................................................................................................................................................................................................................45
Figure 5-6: Bus Entrance...................................................................................................................................................................................................................46
Figure 5-7: Induction Motor Feeder.............................................................................................................................................................................................48
Figure 5-8: Reduced Voltage Reactor Start.............................................................................................................................................................................49
Figure 5-9: Synchronous Motor Feeder.....................................................................................................................................................................................51
Figure 5-10: Sample Lineup – A.....................................................................................................................................................................................................52
Figure 5-11: Sample Lineup – B.....................................................................................................................................................................................................52
Figure 5-12: Tie Breaker and Aux Tie Stack.............................................................................................................................................................................53
Figure 5-13: Bus VTs on Each Side of Tie Breaker................................................................................................................................................................53
Figure 5-14: Feeder Breakers in Upper Compartment......................................................................................................................................................53
Figure 5-15: Bus VT in the Aux Tie Compartment................................................................................................................................................................53
Figure 5-16: Typical Main-Tie-Main Example with Eight Feeder Breakers.............................................................................................................54
Figure 6-1: Breaker Compartment...............................................................................................................................................................................................55
Figure 6-2: Ground Shoe in Breaker Cell...................................................................................................................................................................................56
Figure 6-3: Breaker Position – Disconnected (Green).........................................................................................................................................................56
Figure 6-4: Breaker Position – Intermediate (Yellow)..........................................................................................................................................................56
Figure 6-5: Breaker Position – Connected (Red)....................................................................................................................................................................56
Figure 6-6: Door Stop and Hinges................................................................................................................................................................................................57
Figure 6-7: Optional IR Viewing Window...................................................................................................................................................................................57
Figure 6-8: Optional Lockable T Handle....................................................................................................................................................................................57
Figure 6-9: Disconnect Plug Not Mechanically Interlocked............................................................................................................................................58
Figure 6-10: Disconnect Plug Mechanically Interlocked..................................................................................................................................................58
Figure 6-11: Rear Door Padlocking Provision.........................................................................................................................................................................58
Figure 6-12: Front Door Padlocking Provision........................................................................................................................................................................58
Figure 6-13: Breaker Racking Padlock.......................................................................................................................................................................................58
Figure 6-14: Shutter Padlocking Provision...............................................................................................................................................................................59
Figure 6-15: Open/Close Pushbutton Locked.........................................................................................................................................................................59
Figure 6-16: Open/Close Pushbutton Open............................................................................................................................................................................59
Figure 6-17: CT Mounting in Breaker Compartment ..........................................................................................................................................................59
Figure 6-18: Typical Ring-Type CTs Mounted in SecoGear Breaker Cell..................................................................................................................60
Figure 6-19: Typical Indoor Voltage Transformer................................................................................................................................................................60
Figure 6-20: Rear View of Two high Compartment Showing Cable Trough..........................................................................................................60
Figure 6-21: Cable Trough Opening.............................................................................................................................................................................................61
Figure 6-22: Ground Bus Bar Bolt Locations...........................................................................................................................................................................61
Figure 6-23: SecoVac Test Box.......................................................................................................................................................................................................61
Figure 6-24: Breaker Racking Mechanism...............................................................................................................................................................................61
Figure 6-25: Ground and Test Device.........................................................................................................................................................................................62
Figure 6-26: SecoVac Barcode.......................................................................................................................................................................................................62
Figure 6-27: SecoVac Nameplate.................................................................................................................................................................................................62
Figure 6-28: SecoGear Label...........................................................................................................................................................................................................62
Figure 6-29: Section Cutaway (Height, Width, and Depth)..............................................................................................................................................64
Figure 6-30: SecoGear Installation Drawing – Indoor Anchoring Method..............................................................................................................64
Figure 6-31: SecoGear Primary Indoor Anchoring Method............................................................................................................................................65
Figure 6-32: SecoGear Alternate Indoor Anchoring Method..........................................................................................................................................65
Figure 6-33: Installation Top View................................................................................................................................................................................................65
Figure 7-1: Device, Front View........................................................................................................................................................................................................66
Figure 7-2: Device, Contact Arms.................................................................................................................................................................................................66
TABLE OF TABLES
Table 1-1: Typical Dimensions for Indoor Construction......................................................................................................................................................2
Table 1-2: Applicable American National Standards Institute (ANSI) Standards....................................................................................................3

DET-882 SecoGear Medium-voltage Switchgear Application and Technical Guide
©2017 General Electric All Rights Reserved vii
Table 1-3: Applicable National Electrical Manufacturers Association (NEMA) Standards..................................................................................3
Table 1-4: Permitted Rollout Unit Combinations......................................................................................................................................................................5
Table 2-1: SecoVac VB2+ Vacuum Circuit Breaker Characteristics............................................................................................................................11
Table 2-2: SecoVac Breaker Capacitor Switching Capabilities......................................................................................................................................12
Table 2-3: Altitude Correction Factors* for SecoVac VB2+ Circuit Breakers and SecoGear Switchgear................................................13
Table 3-1: SecoVac VB2+ IEEE Circuit Breaker Control Voltages and Currents....................................................................................................18
Table 3-2: Contact Ratings for MOC, TOC, and Breaker Auxiliary Switches............................................................................................................18
Table 3-3: Simultaneous Breaker Tripping ...............................................................................................................................................................................20
Table 3-4: GE Type HEA Lockout Relay Coil Current Characteristics.........................................................................................................................20
Table 3-5: AC Load Factor for Charger Battery Voltage...................................................................................................................................................20
Table 3-6: Battery Selection Guide...............................................................................................................................................................................................21
Table 3-7: Battery Sizing, Example A...........................................................................................................................................................................................22
Table 3-8: Battery Sizing, Example B...........................................................................................................................................................................................22
Table 3-9: AC Load Estimating Example....................................................................................................................................................................................23
Table 3-10: Heat Loss per Breaker................................................................................................................................................................................................24
Table 3-11: Heat Loss per Section................................................................................................................................................................................................24
Table 4-1: Remote Control Schemes...........................................................................................................................................................................................33
Table 4-2: Single Ratio CTs................................................................................................................................................................................................................33
Table 4-3: Multiple Ratio CTs............................................................................................................................................................................................................34
Table 4-4: ANSI Device Codes..........................................................................................................................................................................................................34
Table 6-1: SecoGear Characteristics...........................................................................................................................................................................................63
Table 7-1: SecoVac VB2+ Vacuum Circuit Breaker Characteristics............................................................................................................................66

DET-882 SecoGear Medium-voltage Switchgear Application and Technical Guide
SecoGear Switchgear Concepts and Basic Configurations
©2017 General Electric All Rights Reserved 1
SECTION 1. SECOGEAR SWITCHGEAR CONCEPTS AND BASIC CONFIGURATIONS
This Application Guide provides information necessary to
help plan and specify medium-voltage power system
switchgear by utilizing SecoGear Metal-clad switchgear.
This publication can be used to write complete
specifications for most switchgear applications. Included is
guidance in equipment layout, ratings, relay protection,
and references to appropriate standards and literature.
General Electric engineering services, under special
contract agreements, will perform power systemstudies,
including the necessary calculations and comparisons.
The first four sections of this guide discuss topics
applicable to any type of medium-voltage metal-clad
switchgear. Information is provided for circuit breaker
ratings and selection, control power requirements, basic
circuit protections considerations, and specific
recommendations for protection, instrumentation, and
control for basic switchgear circuits.
The remaining sections of the application guide explain
SecoGear application and specification. The modular
construction and the use of multifunction relays and
meters are basic to SecoGear and are shown through
application details covering the use of SecoGear
switchgear and SecoVac breakers in basic circuit
applications. Also included are auxiliary unit and power
conductor compartment structuring.
After selecting individual units, an optimum lineup
configuration can be developed using the guidelines given.
A specification procedure, complete with Guide Form
Specifications, is recommended to facilitate the
documentation of SecoGear Metal-clad switchgear
requirements.
Start with your system voltage and current requirements,
and work through the guide in a step-by-step fashion. The
guide’s structure is based on extensive engineering
experience and will serve as a checklist to aid in preparing
complete specifications.
A brief introduction to SecoGear will serve as a useful
starting point to begin the application procedure.
SECOGEAR METAL-CLAD SWITCHGEAR
SecoGear Metal-clad switchgear is designed to house the
latest GE vacuum circuit breaker, SecoVac VB2+, and can
be used for applications on 4.76 kV, 8.25 kV, and 15 kV
power systems for 31.5 kA and 40 kA. A typical section of
SecoGear with a single breaker and rollout compartment is
shown in Figure 1-1.
Figure 1-1: Typical SecoGear 2-High Section
SecoGear metal-clad switchgear is designed with a full IEEE
metal-clad compartment, bus, and cabling isolation.
SecoVac breakers offer the benefits of reliable vacuum
interrupters, low maintenance, and reduced breaker size
and weight.
Specifically, SecoGear switchgear incorporates the
following basic design elements:
•SecoGear provides two-high breaker stacking for
application flexibility and floor space savings

SecoGear Medium-voltage Switchgear Application and Technical Guide DET-882
SecoGear Switchgear Concepts and Basic Configurations
2 ©2017 General Electric All Rights Reserved
•SecoGear utilizes modular construction resulting in one
basic vertical section size, simplifying system planning
and increasing installation savings
•SecoGear features four-high auxiliary arrangements,
providing additional flexibility and use of floor space
•SecoGear allows for intermixing auxiliary and a breaker
compartment in the same vertical section
Certain elements in the switchgear application procedure
are affected by these fundamental design features. Cubicle
stacking, cabling direction, and VT & CPT compartment
considerations are key when translating the one-line
diagram into a valid arrangement of switchgear cubicles,
auxiliary rollouts, and bus connections in a lineup. These
application considerations are necessary as a result of the
equipment design. A brief illustration of SecoGear
switchgear design concepts is provided to assist in
understanding.
Figure 1-2: Section Contents
Table 1-1: Typical Dimensions for Indoor Construction
Height (h)
95 in [2413 mm]
Width (w)
36 in [914 mm]
Depth (d)
95.05 in [2414 mm]
Breakers and auxiliary devices can be accommodated in
the upper and lower compartments, as shown in Figure 1-3
and Figure 1-4, in a variety of configurations.
Figure 1-3: Typical One-High Breaker
A = Main Busbar
Compartment
B = Circuit Breaker
Compartment
C = Cable
Compartment
D = Front Doors
D
D
B
B
A
C
C