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3VA2 400 A
User Manual
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Siemens 3VA1 100 A, 3VA2 160 A, 3VA1 160 A, 3VA2 250 A, 3VA2 400 A User Manual

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3VA molded case circuit breakers
Introduction
1
Description
2
Applications
3
Accessories
4
Service and maintenance
5
Technical specifications
6
Appendix
A
ESD guidelines
B
List of abbreviations
C
Conversion tables
D
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A5E03603177010-02
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Legal information
Warning notice system
DANGER
will
WARNING
may
CAUTION
NOTICE
Qualified Personnel
personnel qualified
Proper use of Siemens products
WARNING
maintenance are required to ensure that the products operate safely and without any problems. The permissible
Trademarks
Disclaimer of Liability
This manual contains notices you have to observe in order to ensure your personal safety, as well as to prevent damage to property. The notices referring to your personal safety are highlighted in the manual by a safety alert symbol, notices referring only to property damage have no safety alert symbol. These notices shown below are graded according to the degree of danger.
indicates that death or severe personal injury
indicates that death or severe personal injury
indicates that minor personal injury can result if proper precautions are not taken.
indicates that property damage can result if proper precautions are not taken.
If more than one degree of danger is present, the warning notice representing the highest degree of danger will be used. A notice warning of injury to persons with a safety alert symbol may also include a warning relating to property damage.
result if proper precautions are not taken.
result if proper precautions are not taken.
The product/system described in this documentation may be operated only by task in accordance with the relevant documentation, in particular its warning notices and safety instructions. Qualified personnel are those who, based on their training and experience, are capable of identifying risks and avoiding potential hazards when working with these products/systems.
Note the following:
Siemens products may only be used for the applications described in the catalog and in the relevant technical documentation. If products and components from other manufacturers are used, these must be recommended or approved by Siemens. Proper transport, storage, installation, assembly, commissioning, operation and
ambient conditions must be complied with. The information in the relevant documentation must be observed.
All names identified by ® are registered trademarks of Siemens AG. The remaining trademarks in this publication may be trademarks whose use by third parties for their own purposes could violate the rights of the owner.
We have reviewed the contents of this publication to ensure consistency with the hardware and software described. Since variance cannot be precluded entirely, we cannot guarantee full consistency. However, the information in this publication is reviewed regularly and any necessary corrections are included in subsequent editions.
for the specific
Siemens AG
Division Energy Management Postfach 32 20 91050 ERLANGEN GERMANY
Order number: 3ZW1012-0VA10-0AC1 Ⓟ 05/2015 Subject to change
Copyright © Siemens AG 2014. All rights reserved
Page 5
Table of contents
1 Introduction................................................................................................................................. 11
2 Description ................................................................................................................................. 15
1.1 About this documentation .................................................................................................. 11
1.2 Product-specific information............................................................................................... 11
1.2.1 Target readers ................................................................................................................... 11
1.2.2 Technical Support ............................................................................................................. 12
1.2.3 Reference documents ....................................................................................................... 12
2.1 Overview - applications and portfolio ................................................................................. 15
2.1.1 Applications and possible uses .......................................................................................... 15
2.1.2 Portfolio ............................................................................................................................. 17
2.1.3 Application examples......................................................................................................... 22
2.1.4 Detailed information about applications and possible uses ................................................. 24
2.1.5 Technical specifications ..................................................................................................... 25
2.1.6 Molded case circuit breakers and accessories in the system .............................................. 28
2.2 Ergonomic design .............................................................................................................. 32
2.2.1 The right circuit breaker for any installation conditions ....................................................... 33
2.2.2 Ergonomic design of circuit breakers, handles and control elements .................................. 36
2.2.3 Wide range of accessories ................................................................................................ 39
2.2.4 Connection technology ...................................................................................................... 41
2.3 Technical details................................................................................................................ 43
2.3.1 Circuit breaker identification............................................................................................... 44
2.3.2 Operation .......................................................................................................................... 50
2.3.3 Design and components - 3VA1 ........................................................................................ 51
2.3.4 Design and components - 3VA2 ........................................................................................ 52
2.3.5 Current limitation ............................................................................................................... 53
2.3.6 Breaking capacity .............................................................................................................. 54
2.4 Selectivity .......................................................................................................................... 56
2.5 Standards and guidelines .................................................................................................. 59
2.5.1 Compliance with standards ................................................................................................ 59
2.5.2 Electromagnetic compatibility ............................................................................................ 60
2.5.3 Certificates ........................................................................................................................ 60
5.4 Ambient conditions ............................................................................................................ 60
2.
2.5.5 Permissible mounting positions.......................................................................................... 62
2.5.6 Safety clearances .............................................................................................................. 64
2.5.7 Degrees of protection ........................................................................................................ 68
2.5.8 Environmental protection ................................................................................................... 68
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Table of contents
3 Applications............................................................................................................................... 105
2.6 Protection system ...............................................................................................................69
2.6.1 Description of functions ......................................................................................................70
2.6.2 Characteristic curves ..........................................................................................................72
2.6.3 Guide to setting the tripping characteristic ..........................................................................74
2.6.4 Overload protection (L) .......................................................................................................76
2.6.5 Short-time delayed short-circuit protection (S) ....................................................................77
2.6.6 Instantaneous short-circuit protection (I) .............................................................................77
2.6.7 Ground-fault protection (G) .................................................................................................77
2.6.8 Neutral conductor protection (N) .........................................................................................78
2.6.9 Zone-selective interlocking ZSI ...........................................................................................81
2.7 Thermal-magnetic trip unit ..................................................................................................84
2.7.1 Thermal trip unit (L) ............................................................................................................84
2.7.2 Magnetic trip unit with short-circuit protection (I) .................................................................84
2.7.3 Application cases and trip unit types ...................................................................................85
2.8 Electronic trip unit ...............................................................................................................86
2.8.1 Connections .......................................................................................................................87
2.8.2 Protection functions ............................................................................................................88
2.8.3 Operator controls ...............................................................................................................90
2.8.4 Load acceptance and load shedding - load management ..................................................100
2.8.5 Measuring with a Rogowski coil ........................................................................................101
3.1 Line protection applications of 3VA molded case circuit breakers ......................................105
3.1.1 Variants............................................................................................................................106
3.1.1.1 Thermal-magnetic trip units ..............................................................................................106
3.1.1.2 Electronic trip units ...........................................................................................................110
3.1.2 Overview of 3VA molded case circuit breakers in line protection applications ....................124
3.2 Use of the 3VA1 breaker as a switch disconnector ...........................................................126
3.2.1 Overview of 3VA1 as switch disconnectors .......................................................................130
3.2.2 Upstream protection of switch disconnectors ....................................................................130
3.3 DC network applications of the 3VA molded case circuit breaker ......................................132
3.3.1 Introduction ......................................................................................................................132
3.3.2 Variants............................................................................................................................133
3.3.3 Breaking capacity with direct current.................................................................................134
3.3.4 Recommended circuit configurations for DC systems .......................................................135
3.4 400 Hz network applications of 3VA molded case circuit breakers ....................................136
3.5 IT system applications of 3VA molded case circuit breakers .............................................138
3.5.1 Selection criteria for 3VA molded case circuit breakers .....................................................138
3.5.2 Fault situation ...................................................................................................................139
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4 Accessories .............................................................................................................................. 141
4.1 Overview of accessories for 3VA molded case circuit breakers ........................................ 141
4.1.1 Accessories groups ......................................................................................................... 141
4.1.2 Possible combinations of of accessories .......................................................................... 142
4.2 Internal accessories......................................................................................................... 146
4.2.1 Mounting locations on 3VA molded case circuit breakers ................................................. 146
4.2.2 Auxiliary and alarm switches............................................................................................ 150
4.2.3 Contact sequence diagrams ............................................................................................ 154
4.2.4 Technical specifications of auxiliary and alarm switches .................................................. 156
4.2.5 Auxiliary releases ............................................................................................................ 158
4.2.6 Time-delay devices for undervoltage releases ................................................................. 164
4.2.7 COM060 communication module ..................................................................................... 164
4.3 Connection system .......................................................................................................... 165
4.3.1 General information about cables and busbars ................................................................ 165
4.3.2 Portfolio of connection components for 3VA molded case circuit breakers ....................... 169
4.3.2.1 General overview ............................................................................................................ 169
4.3.2.2 Front cable connection .................................................................................................... 173
4.3.2.3 Front busbar and cable lug connections........................................................................... 181
4.3.2.4 Rear busbar and cable lug connections ........................................................................... 186
4.3.3 Further connection accessories ....................................................................................... 191
4.3.3.1 Insulating equipment ....................................................................................................... 191
4.3.3.2 Auxiliary conductor terminal ............................................................................................. 199
4.4 Plug-in and draw-out technology...................................................................................... 201
4.4.1 Introduction ..................................................................................................................... 201
4.4.2 Overview of variants / products ........................................................................................ 205
4.4.3 General information .........................................................................................................
4.
4.4 Information about installation, built-on and built-in components ........................................ 207
206
4.4.5 Plug-in technology ........................................................................................................... 208
4.4.5.1 Product description .......................................................................................................... 208
4.4.5.2 Combination with other accessories................................................................................. 214
4.4.6 Draw-out technology........................................................................................................ 215
4.4.6.1 Product description .......................................................................................................... 215
4.4.6.2 Combination with other accessories................................................................................. 224
4.4.7 Accessories for plug-in and draw-out units ....................................................................... 225
4.4.7.1 Description of individual product variants ......................................................................... 225
4.4.7.2 Overview of technical specifications................................................................................. 236
4.4.7.3 Combination with other accessories................................................................................. 237
4.5 Manual operators ............................................................................................................ 238
4.5.1 Opening, closing and resetting the 3VA molded case circuit breaker ................................ 239
4.5.2 Front mounted rotary operator ......................................................................................... 241
4.5.3 Door mounted rotary operator .......................................................................................... 244
4.5.4 Side wall mounted rotary operator ................................................................................... 249
4.5.5 Locking and interlocking for manual operators ................................................................. 251
4.5.5.1 Locking by the handle ...................................................................................................... 251
4.5.5.2 Locking and interlocking by the rotary operator ................................................................ 253
4.5.5.3 Mutual interlocking of 3VA molded case circuit breakers by means of Bowden cables...... 256
4.5.6 Degree of protection ........................................................................................................ 258
4.5.7 Accessories ..................................................................................................................... 259
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4.6 Motor operators ................................................................................................................260
4.6.1 Motor operator MO320 .....................................................................................................260
4.6.1.1 MANUAL, AUTO and LOCK modes ..................................................................................262
4.6.1.2 Opening, closing and resetting the 3VA molded case circuit breaker .................................263
4.6.1.3 Faults, causes of faults and rectification of faults ..............................................................267
4.6.2 Technical specifications ....................................................................................................268
4.7 Locking and interlocking ...................................................................................................269
4.7.1 General information ..........................................................................................................269
4.7.1.1 Locking ............................................................................................................................269
4.7.1.2 Interlocking.......................................................................................................................270
4.7.2 Locking ............................................................................................................................272
4.7.2.1 Padlock device for the handle ...........................................................................................272
4.7.2.2 Cylinder locks for locking the 3VA molded case circuit breaker .........................................273
4.7.3 Front interlocking ..............................................................................................................277
4.7.3.1 Cylinder locks for implementing interlocks between multiple 3VA molded case circuit
breakers ...........................................................................................................................277
4.7.3.2 Sliding bar with Bowden cable: Modules for sliding bar with Bowden cable .......................282
4.7.3.3 Sliding bar ........................................................................................................................285
4.7.4 Rear interlock ...................................................................................................................288
4.8 Residual current devices ..................................................................................................293
4.8.1 Portfolio............................................................................................................................293
4.8.1.1 Possible combinations of residual current devices and 3VA circuit breakers .....................299
4.8.2 Residual current devices for mounting on circuit breakers .................................................300
4.8.2.1 Side mounted residual current devices Basic RCD310 and Basic RCD510 .......................302
4.8.2.2 Loadside residual current devices Basic RCD320 and Basic RCD520 ..............................319
4.8.2.3 Loadside residual current device Advanced RCD820 ........................................................333
4.8.2.4 Technical specifications ....................................................................................................
8.3 Modular residual current device ........................................................................................355
4.
352
4.9 Communication and link-up to other systems ....................................................................360
4.9.1 Description of application and basic function.....................................................................360
4.9.2 3VA concept 3VA-line.......................................................................................................369
4.9.3 Commissioning and testing of electronic trip units using powerconfig ................................375
4.10 EFB300 external function box ...........................................................................................379
4.10.1 General information ..........................................................................................................379
4.10.2 Power supply ...................................................................................................................380
4.10.3 Functions of the digital input and digital outputs ................................................................380
4.10.4 Zone-selective interlocking ZSI .........................................................................................382
4.10.5 <SET> button ...................................................................................................................384
4.10.6 Technical specifications ....................................................................................................391
4.11 Test devices .....................................................................................................................393
4.11.1 The TD300 activation and trip box ....................................................................................394
4.11.1.1 Operation and execution of the tripping function ...............................................................395
4.11.1.2 Technical specifications of TD300 ....................................................................................397
4.11.2 The TD500 test device .....................................................................................................398
4.11.2.1 Operation and execution of test functions .........................................................................403
4.11.2.2 Executing the test functions using a PC and powerconfig .................................................408
4.11.2.3 Parameterizing using the powerconfig software ................................................................408
4.11.2.4 Technical specifications ....................................................................................................409
4.12 External current transformer for N conductor ....................................................................410
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5 Service and maintenance ........................................................................................................... 419
6 Technical specifications ............................................................................................................. 423
4.13 Escutcheon ..................................................................................................................... 411
4.13.1 Product description .......................................................................................................... 412
4.13.2 Labeling plate .................................................................................................................. 414
4.14 DIN rail adapter ............................................................................................................... 415
4.14.1 Introduction ..................................................................................................................... 415
4.14.2 Information about installation, assembly and attachment ................................................. 416
5.1 Notes .............................................................................................................................. 419
5.2 Regular maintenance ...................................................................................................... 419
5.3 Maintenance following tripping of a molded case circuit breaker....................................... 421
5.4 Fault diagnostics ............................................................................................................. 422
6.1 Circuit diagrams .............................................................................................................. 423
6.1.1 3VA1 molded case circuit breakers .................................................................................. 423
6.1.1.1 Basic units ....................................................................................................................... 423
6.1.1.2 Accessories ..................................................................................................................... 426
6.1.1.3 Example: 3VA1 molded case circuit breaker with built-on/built-in accessories .................. 431
6.1.2 3VA2 molded case circuit breakers .................................................................................. 432
6.1.2.1 Basic units ....................................................................................................................... 432
6.1.2.2 Accessories ..................................................................................................................... 433
6.1.2.3 Example: 3VA2 molded case circuit breaker with built-on/built-in accessories .................. 443
6.1.3 Application examples....................................................................................................... 444
6.1.3.1 Main switch application with EMERGENCY-STOP function in accordance with
Machinery Directive IEC/EN 60204-1 ............................................................................... 444
6.1.3.2 Electrical interlocking of two 3VA molded case circuit breakers with undervoltage
releases .......................................................................................................................... 445
6.2 Dimensional drawings ..................................................................................................... 446
6.2.1 Dimensions of basic units ................................................................................................ 446
6.2.1.1 3VA10 and 3VA11 ........................................................................................................... 446
6.2.1.2 3VA12 ............................................................................................................................. 449
6.2.1.3 3VA20 ............................................................................................................................. 450
6.2.1.4 3VA23 ............................................................................................................................. 452
6.2.2 Dimensions of accessories .............................................................................................. 453
6.2.2.1 Connection technology .................................................................................................... 453
6.2.2.2 Plug-in and draw-out units ............................................................................................... 460
6.2.2.3 Manual operators ............................................................................................................ 463
6.2.2.4 Motor operators ............................................................................................................... 471
6.2.2.5 Locking and interlocking ..................................................................................................
6.
2.2.6 Residual current devices ................................................................................................. 478
6.2.2.7 Communication and system integration ........................................................................... 483
6.2.2.8 EFB300 external function box .......................................................................................... 484
6.2.2.9 Test devices .................................................................................................................... 485
6.2.2.10 External current transformer for N conductor ................................................................... 485
6.2.2.11 Escutcheon ..................................................................................................................... 486
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9
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Table of contents
A Appendix .................................................................................................................................. 505
B ESD guidelines .......................................................................................................................... 507
C List of abbreviations ................................................................................................................... 509
D Conversion tables ...................................................................................................................... 515
Glossary ................................................................................................................................... 519
Index ........................................................................................................................................ 525
6.3 Power losses ....................................................................................................................487
6.3.1 Power losses of 3VA1 molded case circuit breakers .........................................................487
6.3.2 Power losses of 3VA2 molded case circuit breakers .........................................................488
6.4 Derating and temperature compensation ..........................................................................489
6.4.1 Derating of 3VA1 molded case circuit breakers .................................................................489
6.4.2 Temperature compensation with thermal-magnetic trip units of the TM 2-series ................491
6.4.3 Use of terminals with auxiliary conductor connection ........................................................496
6.4.4 Additional correction factors with frequencies other than 50/60 Hz for 3VA1 molded
case circuit breakers ........................................................................................................496
6.4.5 Correction factors with direct current for the thermal-magnetic trip units of 3VA1
molded case circuit breakers ............................................................................................498
6.4.6 Derating for the 3VA1 switch disconnector ........................................................................499
6.4.7 Derating for the electronic trip units of 3VA2 molded case circuit breakers ........................501
A.1 Standards and approvals ..................................................................................................505
B.1 Electrostatic sensitive devices (ESD) ................................................................................507
C.1 Table of abbreviations ......................................................................................................509
3VA molded case circuit breakers
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1
1.1

About this documentation

3VA molded case circuit breakers
Benefits
Scope of validity of this document
1.2

Product-specific information

1.2.1

Target readers

Target readers of this documentation
As part of our portfolio of cost-effective power distribution products, we are offering extremely flexible molded case circuit breakers designed to protect personnel and material assets.
We can supply exactly the right molded case circuit breaker for every application.
● Maximum flexibility thanks to the modular design of the internal and external accessories
● Outstanding selectivity, for example, makes planning very simple
● State-of-the-art manufacturing techniques
● All-round product support provided by integrated online support tools
This manual is a reference manual for technical information that users will need in order to configure and operate 3VA molded case circuit breakers.
The information contained in this manual is provided for the benefit of:
● Users
● Cubicle manufacturers
● Switchgear manufacturers
● Maintenance personnel
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Introduction
1.2.2

Technical Support

1.2.3

Reference documents

Further documents
Title
Article number
Link
1.2 Product-specific information
You can find further support on the Internet at:
)
Technical Support (http://www.siemens.com/lowvoltage/technical-support
You will find further information in the following documents:
Table 1- 1 Reference documents
3VA molded case circuit breakers catalog DE E86060-K8220-E480-A3 3VA molded case circuit breaker catalog
www.siemens.com/lowvoltage/infomateri
EN E86060-K8220-E480-A2-7600
3VA molded case circuit breaker operat­ing instructions
3VA Communication system manual DE 3ZW1012-0VA20-0BB0 3VA molded case circuit breaker docu-
3VA molded case circuit breaker tables (updated daily)
Automatic transfer control device ATC5300 - Manual
ATSE - Remote Control Software Manual DE A5E02469028-01 ATSE - Remote Control Software Manual
ATSE - Modbus Communication Protocol DE A5E02469001-01 ATSE - Modbus Communication Protocol
Grundlagen der Niederspannungsschalt­technik (Fundamentals of Low-Voltage Switchgear and Controlgear), Siemens AG © 2008
Hartmut Kiank, Wolfgang Fruth: Pla­nungsleitfaden für Energieverteilungsan­lagen (Planning Guide for Power Distribution Plants), Publicis Publishing
3VA molded case circuit breaker docu-
EN 3ZW1012-0VA20-0BC0
3VA molded case circuit breaker docu-
DE A5E02469034-01 Automatic transfer control device EN A5E02469035-01
EN
EN
— —
ISBN: A19100-L531-B115 —
(
al)
mentation (
Documentation)
mentation (
Documentation)
mentation (
Documentation)
ATC5300
http://support.automation.siemens.com/
(
WW/view/de/41909986/0/en)
http://support.automation.siemens.com/
(
WW/view/de/41909978)
(
http://support.automation.siemens.com/
WW/view/de/40761679)
http://www.siemens.com/3VA-
http://www.siemens.com/3VA-
http://www.siemens.com/3VA-
3VA molded case circuit breakers
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Page 13
Introduction
Title
Article number
Link
1.2 Product-specific information
Switching, Protection and Distribution in Low-Voltage Networks, substantially extended and revised edition 1997
Siemens: Residual Current Protective Devices, Low-Voltage Circuit Protection Technology Primer Siemens AG © 04 / 2009
ISBN 3-89578-041-3 —
E10003-E38-9T-B3011 —
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Page 14
Introduction
1.2 Product-specific information
3VA molded case circuit breakers
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2
2.1

Overview - applications and portfolio

2.1.1

Applications and possible uses

This chapter provides an overview of all molded case circuit breakers in the 3VA portfolio and describes the potential areas of application for different circuit breaker models.
The topics discussed in this chapter are listed below:
● Applications and possible uses
● Portfolio
● Possible configurations
● Detailed information about applications and possible uses
● Technical specifications
● Molded case circuit breakers and accessories in the system
The two tables below show examples of applications and possible uses for the new 3VA molded case circuit breakers.
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Description
Possible uses
Functions and applications
2.1 Overview - applications and portfolio
3VA molded case circuit breakers can be deployed in various fields where they perform a variety of different protection tasks. The following table (sorted according to breaking capacity) shows the areas in which 3VA molded case circuit breakers are used:
3VA molded case circuit breakers are used in a variety of functions, as shown in the table below:
3VA molded case circuit breakers
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Description
2.1.2

Portfolio

Sizes
2.1 Overview - applications and portfolio
Molded case circuit breakers are primarily designed for the following applications:
● Subdistribution systems
● Industrial distribution systems
● Final distribution systems
● On-site isolation
● Use in machines
The integrated 3VA portfolio consists of two different series of molded case circuit breakers in five different rated operational current versions (sizes).
The new 3VA molded case circuit breakers set new standards in flexibility and the variety of modular accessories available. Standardized accessories suitable for use with several sizes of circuit breaker from all the 3VA ranges help to cut costs and save time.
The new 3VA1 molded case circuit breakers are available in 1 to 4-pole versions (3VA1 160 A) or in 3 and 4-pole versions (3VA1 100 A or 3VA1 250 A). The new 3VA2 molded case circuit breakers are available in 3 and 4-pole versions.
The circuit breakers are available with rated operational currents ranging from 16 A to 630 A and rated voltages up to 690 V, depending on the series and size.
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Description
3VA1 molded case circuit breakers
Features
Compact dimensions
Thermal-magnetic trip units
2.1 Overview - applications and portfolio
The new 3VA1 molded case circuit breakers reliably perform all the tasks associated with line protection.
The key features of the 3VA1 series are:
● Compact design
● Depending on size: 1 and 2-pole versions in size 160 A, 3 and 4-pole versions in sizes
100 A, 160 A and 250 A
● Depending on size: Breaking capacity of 16 kA ... 70 kA at 415 V, 3 or 4-pole breakers
and 36 kA at 240 V,1-pole breakers
● Fixed-mounted, plug-in version
● Thermal-magnetic trip units
● AC/DC applications
● No derating up to +50 °C
● Modular and easy-to-fit internal accessories with diverse functions
● Uniform accessories platform across all 3VA molded case circuit breakers
Thanks to a mounting depth of 70 mm and a cover size of 45 mm, the 3VA1 molded case circuit breakers of sizes 100 A, 160 A and 250 A are ideal for protecting cables and lines in the plant area, especially for the INSTA electrical installation area. For these applications, there is also a wide range of accessories available such as adapters for installation on DIN rails, as well as residual current devices (RCD310 and RCD510) that can be side mounted.
3VA1 molded case circuit breakers are equipped with a thermal-magnetic trip unit which provides overload and short-circuit protection. This has been developed for implementing economical, cost-efficient installations up to 250 A. It is suitable for use in three-phase networks, AC networks, 400 Hz applications, and with DC currents.
3VA molded case circuit breakers
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Description
3VA2 molded case circuit breakers
Features
2.1 Overview - applications and portfolio
The new 3VA2 molded case circuit breakers reliably perform all the tasks associated with line and generator protection.
This series is designed for applications with more exacting requirements:
● Increased breaking capacity
● Excellent selective protection
● Integrated metering function
● Connection to a fieldbus communication system
The most important features of the 3VA2 series are:
● Compact dimensions
● 3 and 4-pole versions
● Four breaking capacity classes from 55 kA … 150 kA
● Fixed-mounting, plug-in technology, draw-out technology
● Depending on size: Selective tripping at rated operational current difference 1 : 2.5
● Electronic Trip Units
● Retrofittable communication for ETU 5-series and 8-series
● Depending on the ETU: Integrated metering function
● AC applications
● No derating up to +50 °C
● Modular and easy-to-fit internal accessories with diverse functions
● Uniform accessories platform across all 3VA molded case circuit breakers
● Electronic Trip Units (ETU) with different setting values
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Description
Compact dimensions with function expansions
Selective contact system
Electronic Trip Unit (ETU)
2.1 Overview - applications and portfolio
In addition to its expanded functionality, the 3VA2 molded case circuit breaker also comes with compact dimensions for fixed mounting, as a plug-in version and a draw-out version.
A cover size of 70 mm for the door cutout and a complete selection of breaking capacity classes from 55 kA to 150 kA at 415 V AC provide the necessary flexibility for planning.
Despite its compact size, the circuit breaker offers the following benefits:
● Extremely high breaking capacity
● Extremely good selectivity
● Electronic trip units, versions with and without integrated metering function and optional
fieldbus communication interface
With its contact system, the 3VA2 molded case circuit breaker is designed for fast selectivity tripping. The selective contact system ensures the following:
● Dynamic instantaneous short-circuit range
● High breaking capacity
● Selective protection response of the molded case circuit breakers in relation to each other
● Selective protection response of the molded case circuit breakers in relation to other
protection devices such as downstream low-voltage fuses, etc.
The current sensor of the 3VA2 comprises an iron-cored transformer for the internal power supply and a Rogowski coil for precise current measurement. Each transformer can be optimized accordingly for its specific task. Thanks to the high accuracy of current measurement, the 3VA2 molded case circuit breaker is suitable for power/energy measurement. In addition, finer adjustment of ground fault current monitoring is possible.
The Electronic Trip Units (ETUs) provide the following protection functions:
● Overload protection L ("L" = Long-time delay)
Adjustable in steps from 40% to 100% of the rated operational current of the molded case circuit breaker.
● Short-time delayed short-circuit protection S ("S" = Short-time delay) for time-selective
response in case of a short circuit
● Instantaneous short-circuit protection I ("I" = instantaneous):
● Protection of the neutral conductor against overload and short-circuit ("N" = neutral)
● Protection against residual currents to ground ("G" = Ground fault).
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Description
Energy management and communication
2.1 Overview - applications and portfolio
The Electronic Trip Units (ETUs) provide the following energy management and communication functions:
● Metering functions
● Communication
● Flexible, local, digital inputs and outputs via the EFB300 external function box
● Software commissioning support with powerconfig
● Testing and archiving with the TD300 and TD500 test devices (with powerconfig)
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Description
2.1.3

Application examples

2.1 Overview - applications and portfolio
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Description
2.1 Overview - applications and portfolio
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Description
2.1.4

Detailed information about applications and possible uses

See also
2.1 Overview - applications and portfolio
Applications (Page 105)
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Description
2.1.5

Technical specifications

2.1 Overview - applications and portfolio
O. r. On request
1)
A side plate must be installed (see chapter Insulating equipment (Page 191)) if the installation conditions on the
right-hand side are such that the device is not finger-safe.
2)
In 125 A, 160 A: I
/ Ics = 36 kA / 36 kA
cu
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Description
2.1 Overview - applications and portfolio
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Description
2.1 Overview - applications and portfolio
O. r. On request
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Description
2.1.6

Molded case circuit breakers and accessories in the system

2.1 Overview - applications and portfolio
The new 3VA molded case circuit breakers come with a large portfolio of internal and external accessories which can be installed flexibly in any size of circuit breaker (depending on the type of accessory).
The table below indicates which accessories are compatible with particular molded case circuit breakers, and which sizes of breakers are compatible with the same accessory:
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Description
2.1 Overview - applications and portfolio
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Description
Overview of accessories in the system
2.1 Overview - applications and portfolio
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Description
2.1 Overview - applications and portfolio
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Description
2.2
Ergonomic design
Integrated system

2.2 Ergonomic design

This chapter provides an overview of the ergonomic design features of the new 3VA molded case circuit breakers and explains what makes them so special.
The topics discussed in this chapter are listed below:
● Optional installation variants
● Color-coded indication of switching position in the draw-out unit
● Clear status indication
● Active illumination
● Ergonomic handle
● Color-coded control elements
● Broad range of accessories
● Connection options
With their technical features and functional scope, the new 3VA molded case circuit breakers break new ground - but they also set new standards in ergonomic design.
When it comes to operation, functionality and installation, the new 3VA series is a fully integrated system. This principle is embodied in the basic units and in all internal and external accessories.
The benefits offered by the internal and external accessories available for the 3VA molded case circuit breakers are:
● Standardized methods of operation
● Standardized scope of functions
● Standardized installation procedures
● Standardized accessories for all breaker versions from 100 A to 630 A (e.g. auxiliary
switches, auxiliary releases, etc.)
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Description
2.2.1

The right circuit breaker for any installation conditions

2.2 Ergonomic design
The new series of molded case circuit breakers can be equipped with additional components so that they can be installed as fully functional switches in any location, a feature of the product which affords maximum flexibility to system planners.
The following components can be installed to suit the installation location:
● Handle
● Front mounted rotary operator
● Door mounted rotary operator
● Side wall mounted rotary operator
● Motor operator
When the 3VA molded case circuit breaker is in the OFF position, it reliably disconnects all current paths of the circuit in accordance with IEC 60947-2 and IEC 60204-1 (VDE 0113). In the event of overvoltage between input and output, the reduced clearances prevent leakage currents at the surface and ensure that the dielectric strength is not degraded.
The main switch functionality is not diminished by installation of the following accessories:
● Motor operator
● Manual operator
● Residual current device
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Description
Optional installation variants
2.2 Ergonomic design
3VA molded case circuit breakers are available in the following installation variants:
● Fixed mounted ①
● Plug-in technology
● Draw-out technology
All variants offer the full range of functions, e.g. they can be equipped with every kind of accessory. In addition, the last two variants are designed to allow speedy molded case circuit breaker replacement for maintenance purposes or visual indication of the electrical isolation in the main circuit.
②
③
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Description
Indication of switching positions in the draw-out unit
2.2 Ergonomic design
The picture below illustrates the colors used to indicate the switching position in the draw-out unit:
The switching position is indicated in a window of the draw-out unit and is clearly color­coded, enabling immediate identification of the current switching position of the molded case circuit breaker.
The draw-out unit has three switching positions:
● CONNECT:
The molded case circuit breaker is connected to the main circuit.
● TEST:
In the TEST position, the main contacts of the molded case circuit breaker are not connected to the main circuit, but only to the auxiliary circuit. It is therefore possible to check that the auxiliary circuit is functioning properly when the main circuit is open.
● DISCONNECT:
The molded case circuit breaker is not connected to the main circuit nor to the auxiliary circuit.
● UNBLOCK:
The molded case circuit breaker is not in any of the positions defined above and can be moved by means of the crank handle.
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Description
Motor operator for remote control
2.2.2

Ergonomic design of circuit breakers, handles and control elements

Ergonomic handle
2.2 Ergonomic design
3VA molded case circuit breakers can also be controlled remotely. Whether the circuit breaker is controlled from "just" the other side of the closed cubicle door, or the breaker is switched on via a control room, operator panel, etc., is irrelevant.
Motor operators are available as accessories for remote control of the circuit breakers.
With its wide surface area, the ergonomic handle is designed to assist manual operation of the circuit breaker. The white strip around the edge of the handle makes it easy to identify in conditions of poor visibility. The additional rated operational current information stamped on the white strip also significantly eases identification of the circuit breaker when it is one of many breakers in a large switchboard installation.
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Description
Clear status indication
Active illumination
2.2 Ergonomic design
The possible switching positions of manual rotary operators are listed below:
● ON - red marking
● TRIP - yellow marking
● OFF - green marking
The handle clearly engages in one of these positions depending on the status of the molded case circuit breaker. The switching positions are color-coded so that you can identify the status of the circuit breaker at a glance.
You can retrofit an active illumination kit to manual rotary operators. The illuminated indicator in the rotary handle signals the relevant switching position in the colors red, yellow and green. This provides clear visualization of the switching position on-site in conditions of poor visibility.
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Description
Color-coded control elements
2.2 Ergonomic design
The control elements on the thermal-magnetic and electronic trip units are color-coded.
The color of each control element indicates that it performs a specific function, helping you to make the required settings quickly.
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Description
2.2.3

Wide range of accessories

Color coding of accessories
2.2 Ergonomic design
The internal accessories (e.g. alarm and auxiliary switches, auxiliary releases, etc.) all belong to one family and can be installed on any size of 3VA1 or 3VA2 circuit breaker. The accessories are designed for quick and easy installation. The components are coded by color and design to ensure that they are always installed at the correct position in the circuit breaker.
The internal accessories are color coded to clearly indicate their specific function.
A system of color coding has been used to clearly identify the specific functions of individual accessories:
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Description
Fast assembly of motor operators
2.2 Ergonomic design
The cylinder lock and communication accessories included with the internal accessories in the picture above are explained in chapters Locking and interlocking (Page 269) and Communication and link-up to other systems (Page 360).
The motor operators have been designed for quick and easy assembly and disassembly. The internal accessories are therefore easily accessible.
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Description
2.2.4

Connection technology

①
⑦
②
⑧
③
⑨
④
⑩
⑤
⑪
⑥
⑫
2.2 Ergonomic design
A large selection of connection systems is available for the new series of 3VA molded case circuit breakers.
The supported cable cross-sections are based on the size of the molded case circuit breaker and the cable terminals used. The terminals are fitted either internally or externally to the molded case circuit breaker.
The connection technology is easy to integrate in the new series of 3VA molded case circuit breakers.
With it you can implement various front and rear main conductor connections for the molded case circuit breakers in all types of installation (fixed-mounted, plug-in and draw-out).
Box terminal Circular conductor terminal Circular conductor terminal, large Lug terminal Lug terminal, right-angled Front connection bars edgewise
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Front connection bars extended Front connection bars broadened Rear terminal flat Rear connecting stud Circular conductor terminal for 2 cables Circular conductor terminal for 6 cables
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Description
Cables and busbars
2.2 Ergonomic design
The new series of 3VA molded case circuit breakers are designed for connection to a variety of different cables and busbars:
● Different cable types, e.g.
① Circular conductor
–
② Sector-shaped conductor
–
③ Stranded
–
④ Finely stranded
–
● ⑤ Busbars
– Rigid
– Laminated or flexible
⑥ Laminated copper bar
●
● Different materials
– Copper cables
– Aluminum cables
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Description
2.3
Technical details

2.3 Technical details

A summary of the technical features of 3VA molded case circuit breakers can be found in this chapter.
The topics discussed in this chapter are listed below:
● Circuit breaker identification
● Operation
● Design and components – 3VA1
● Design and components – 3VA2
● Current limitation
● Breaking capacity
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Description
2.3.1

Circuit breaker identification

Circuit breaker labeling
①
④
②
⑤
③
2.3 Technical details
Each 3VA molded case circuit breaker can be clearly identified from various labels and plates attached to the unit.
Each 3VA molded case circuit breaker has labels displaying all the important technical information, enabling unique identification:
Connection information label ETU connection designations Label insert (in accessories compartment)
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Key electrical data Internal accessories label
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Description
Front panel: Labeling
①
⑦
②
⑧
③
⑨
④
⑩
⑤
⑪
⑥
Knowledge Manager
2.3 Technical details
The following information is displayed on the front panel of the circuit breaker:
Circuit breaker designation Approvals Rated operational current Knowledge Manager (see below) Rated operational current Date of manufacture
A QR code is attached in a clearly visible location to every 3VA molded case circuit breaker. This code can be scanned with a smartphone or a tablet PC. For the full range of QR code functions, use the "Industry Support" app supplied free of charge by Siemens.
It allows you to directly view or download all relevant product information.
Product version Article number Trip unit type Size and breaking capacity class Key electrical data
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Description
①
③
②
④
2.3 Technical details
The key electrical data label on the molded case circuit breaker displays the following information:
IEC breaking capacity values at various volt-
ages
Frequency, utilization category
Insulation data
Supported standards
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Description
Connection information label
①
③
②
④
2.3 Technical details
The connection information label displays the following information:
Information about cable connections Code for production
Article number for operating instructions Article number
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Description
Label insert
2.3 Technical details
The label insert can be found in the right-hand accessories compartment. When an accessory (e.g. motor operator or manual operator) is installed on the circuit breaker, this label can be attached to the accessory.
The label insert displays the following information:
● Information about the molded case circuit breaker
● Article number
● Key electrical data
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Internal accessories label
2.3 Technical details
You can make a note of the number of installed accessories on the internal accessories label. This will enable you to ascertain which accessories are installed without removing the lid of the accessories compartment and to use the information, for example, to reorder components.
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Description
2.3.2

Operation

①
ON: Main contacts closed
③
OFF: Main contacts open
②
TRIP: Switching position following a trip
④
PUSH TO TRIP: Initiates a mechanical trip
Reclosing the circuit breaker contacts from the TRIP position
Free tripping
2.3 Technical details
The main contacts of the molded case circuit breakers are opened and closed by means of a handle mounted on the front of the unit. All contacts open and close simultaneously on all 3VA molded case circuit breakers in response to the following events:
● The handle is moved from OFF to ON.
● The handle is moved from ON to OFF.
● The tripping mechanism is activated by a trip unit.
● The tripping mechanism is activated by auxiliary releases (e.g. shunt trips, trip units).
Follow the steps below to reclose the circuit breaker contacts from the TRIP position:
1. Move the handle to the OFF position.
2. Move the handle to the ON position.
→ The breaker contacts are now closed.
All 3VA molded case circuit breakers have a free tripping capability. This function ensures that the breaker cannot be prevented from tripping even if the operator blocks or is held manually in the ON position or if the breaker is about to close.
Follow the steps below to test the free tripping function in order to verify that the breaker's mechanical release system is working correctly:
1. Move the handle to the ON position.
2. Hold the handle in the ON position and press the button marked <PUSH TO TRIP>.
→ The circuit breaker trips and opens the main contacts.
→ The handle moves quickly into the TRIP position as soon as you release it.
Failure of the molded case circuit breaker to trip indicates that it is defective and must be replaced.
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Description
2.3.3

Design and components - 3VA1

①
④
②
Breaker mechanism with handle
⑤
Arc plates
③
⑥
2.3 Technical details
The design of the 3VA1 molded case circuit breaker is illustrated in the diagram below:
Main connections
Trip unit: TMTU
Rotary contact system
Pole cassette enclosure
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Description
2.3.4

Design and components - 3VA2

①
⑤
②
⑥
③
⑦
④
2.3 Technical details
The design of the 3VA2 molded case circuit breaker is illustrated in the diagram below:
Main connections Breaker mechanism with handle Trip unit: ETU Rotary contact system
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Arc plates Maglatch Current sensor
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Description
2.3.5

Current limitation

①
②
③
2.3 Technical details
The term "current limitation" refers to the action of limiting the peak value of the prospective impulse short-circuit current i
to a lower let-through current iD.
p
The compact design of the breakers has been made possible by their excellent current limiting capabilities. In the event of a short circuit, the molded case circuit breaker significantly reduces the magnitude of let-through current, i.e. it reduces the current loading of downstream equipment (lower thermal load, fewer dynamic forces). The level of let­through energy is also reduced to a considerable extent.
3VA molded case circuit breakers are designed with a current-limiting capability. IEC EN 60947-2 (VDE 0660-101), section 2.3, page 12, defines current-limiting molded case circuit breakers in the following way:
"Circuit breaker that prevents the let-through current from achieving the prospective peak value over a specific current range, and that limits the let-through energy (I
2
t) to a value that
is lower than the let-through energy of one half-wave of the symmetrical prospective current."
Unlimited current Peak value of limited current Limited current
Let-through current
i
D
i
Unlimited impulse short-circuit current
p
t
Break time
a
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Description
Double-rotary contact system
①
②
③
2.3.6

Breaking capacity

2.3 Technical details
To achieve excellent current limiting, the 3VA molded case circuit breakers are equipped with a double-rotatory contact system that opens dynamically on its own above the specified disengaging currents on the principle of magnetic repulsion before the expected peak value of the short-circuit current is reached. These limits have been coordinated and optimized to suit the overall device characteristics. This substantially reduces the thermal and mechanical loading on the molded case circuit breaker and the electrical installation.
Fixed contacts Rotary contact system Arc splitter chute
The switching pole cassettes are optimized for high breaking capacity, and their double­rotary contact system design enables extremely good current limiting thanks to the build-up of peak arc voltage generated at both contacts in the event of a short-circuit. This results in significant limitation of the let-through energy I²t and the let-through current.
The rated ultimate short-circuit breaking capacity Icu is the maximum value of the short-circuit current which the protective device is capable of disconnecting in accordance with regulations. Up to this value, the protective device is also allowed to be used in a network.
The new 3VA molded case circuit breakers are available with identical external dimensions but various breaking capacity classes according to size and rated operational current range.
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Description
Switching capacity of the 3VA1 series
Switching capacity of the 3VA2 series
2.3 Technical details
O. r. On request
1)
In 125 A, 160 A: I
/ Ics = 36 kA / 36 kA
cu
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Description
2.4
Selectivity
Selective behavior

2.4 Selectivity

Switching devices connected in series, e.g. molded case circuit breakers and fuses, work in a coordinated manner to ensure that switching devices are tripped successively. The closest, upstream switching device before the location of the short-circuit must trip. The other switching devices on the same current run do not trip. The purpose of selectivity is to minimize the effects of a fault in terms of its duration and the area affected by the fault.
Selectivity is achieved when the circuit breakers are matched to each other by means of selection, configuring and trip settings in such a way that, in the event of a fault, only the breaker closest to the location of the fault trips.
The selective behavior of molded case circuit breakers is mainly influenced by the following factors:
● Tripping value settings of the trip unit
● Tripping and break times
● Let-through current values
● Modes of switching of the relevant circuit breakers
Short-circuit location
– Zero-current interrupter
– Current limiter
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2.4 Selectivity
The selective behavior of circuit breakers can be implemented technically by a variety of selectivity concepts:
● Current selectivity
The selectivity can be calculated in the overload range by comparing the time/current characteristics. In the short-circuit range, this comparison leads to values that are too low. The reason for this is that the trip unit behaves differently in the case of short-circuit currents compared to its long-term behavior, e.g. in the case of overload.
If the short-circuit currents differ sufficiently at the installation points of two molded case circuit breakers, the instantaneous short-circuit releases can normally be set such that if a short-circuit occurs behind the downstream circuit breaker, only this downstream breaker trips.
If the short-circuit currents are approximately the same at the installation points of the molded case circuit breakers, the grading of the tripping currents of the short-circuit releases only enables selectivity up to a specific short-circuit current .
This current is referred to as the ultimate selectivity value I
.
s
● Time selectivity
Selectivity can be achieved by time selectivity up to the threshold values of the instantaneous short-circuit releases. To achieve this, the upstream circuit breaker requires delayed short-circuit releases, so that in the event of a fault, only the downstream circuit breaker will disconnect the part of the electrical installation affected by the fault from the supply.
Both the tripping delays and the tripping currents of the short-circuit releases are graded.
● Zone-selective interlocking - ZSI
Selective behavior is achieved by installing parallel control cables between the molded case circuit breakers. The electronic trip units then use a fast signal link to determine priorities in the tripping sequence.
Zone Selective Interlocking (ZSI) has been developed by SIEMENS in order to prevent unacceptably long tripping times when several molded case circuit breakers are connected in series.
ZSI enables the tripping delay to be reduced to 50 ms for the circuit breaker upstream from the location of the short circuit.
● Dynamic selectivity
This method is based on evaluation of the arc power which is generated in the arc chute when the contacts open dynamically in response to a short circuit. During this process, a smaller sized downstream molded case circuit breaker converts more energy in the arc chute than the larger, upstream molded case circuit breaker. A selective trip unit evaluates the energy conversion in both molded case circuit breakers. The downstream molded case circuit breaker trips, while the contacts of the upstream circuit breaker close again. Since both molded case circuit breakers perform a current limiting function, the residual current limit imposed in practice is higher than the limiting action specified for the individual molded case circuit breakers.
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Description
Full selectivity
Partial selectivity
Selectivity with 3VA2 molded case circuit breakers
2.4 Selectivity
There is an increasing demand for full selectivity in order to safeguard continuity of service by power distribution systems. A power system is said to be fully selective if only the protective device located upstream of the fault location when viewed in the direction of energy flow, i.e. from the infeed to the load, trips in the event of a fault.
Full selectivity always refers to the short-circuit current occurring at the installation point.
A system is said to be partially selective when selective tripping in response to a system fault is not ensured up to the maximum ultimate short-circuit breaking capacity I devices. Selectivity is then ensured only up to a certain I
current value (ultimate selectivity
s
value). If the calculated prospective short-circuit current at the location of installation of the downstream protective device is lower than the ultimate selectivity value specified for the switching devices, then it is still possible to describe the system as fully selective.
If the values determined by the short-circuit current calculation (e.g. according to IEC/EN 60909, DIN VDE 0102) at the installation point of the downstream circuit breaker lie below the ultimate selectivity value listed in the respective table for the selected combination, selectivity is assured for all possible short circuits at the installation point.
of the switching
cu
If the calculated short-circuit current at the installation point is higher than the ultimate selectivity value, selective tripping by the downstream circuit breaker is only assured up to the value listed in the table. A judgment must be made as to whether the value can be considered to be sufficient because the probability of the maximum short-circuit occurring is low, for example. Otherwise, a circuit breaker combination should be chosen whose selectivity limit lies above the maximum short-circuit current.
Series 3VA2 circuit breakers are designed to deliver excellent selective tripping combined with optimum current limiting and outstanding breaking capacity.
3VA2 molded case circuit breakers have been specifically designed to meet the following requirements:
● System-wide, high selectivity with a rated operational current differential of 1 : 2.5 up to
the miniature circuit breaker
● Selectivity in combination with high current limiting and high breaking capacity
● Cost-effective design / configuring of selective power distribution systems
These molded case circuit breaker requirements are achieved in engineering terms as follows:
● Rotary, double-break contact system for highly dynamic opening response
● Coordinated electronic trip units
● Dynamic selectivity
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Electronic trip units and fast trip units
2.5
Standards and guidelines
2.5.1

Compliance with standards

2.5 Standards and guidelines

Depending on use of molded case circuit breakers with a rated operational current differential in a ratio of at least 1 : 2.5 and selection of suitable breaking capacity classes, you can achieve selective tripping of the area of the installation directly affected by the fault up to the maximum ultimate short-circuit breaking capacity.
You can find information on selectivity values for 3VA2 molded case circuit breakers on the Internet under the link for 3VA documentation (
Documentation).
As a protective device, the molded case circuit breaker is required to clear electrical faults in the system. For this purpose, series 3VA2 circuit breakers are equipped with intelligent electronic trip units which can be combined with metering functions.
The tripping characteristic of the electronic trip units can be finely and flexibly adjusted. In the event of short circuits, a fast trip unit also responds according to the arc power from the arc chute. This selective trip unit ensures that major short circuits are cleared more quickly, while at the same time ensuring that medium short circuits are interrupted selectively.
http:/www.siemens.com/3VA-
All the standards and guidelines with which 3VA molded case circuit breakers comply are summarized in this chapter.
The topics discussed in this chapter are listed below:
● Compliance with standards
● Electromagnetic compatibility
● Ambient conditions
● Degrees of protection
The standards fulfilled by the 3VA molded case circuit breakers include:
● IEC / EN 60947-1
● IEC / EN 60947-2
● IEC / EN 60947-2, Annexes B, H and M
● IEC / EN 60947-3
● IEC / EN 60947-6-1
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2.5.2

Electromagnetic compatibility

2.5.3

Certificates

2.5.4

Ambient conditions

Pollution degree
Ambient temperature
Special climatic requirements
2.5 Standards and guidelines
The 3VA molded case circuit breakers meet the requirements of the following standards:
● CISPR11, Class A and Class B
● IEC / EN 60947-1, Appendix S
● IEC / EN 60947-2, Appendices B, F, J and N
The 3VA molded case circuit breakers are adequately resistant to the following factors:
● Electrostatic charge
● Electrostatic discharge
● Electromagnetic waves, e.g. from transmission systems, mobile phones, radio telephone
sets and radar systems
● Overvoltage, e.g. caused by lightning
● Voltage surges
You can find information on the available certification (CE, UL, CSA, FM, marine approvals) on the Internet (http://support.automation.siemens.com/WW/view/en/54137334/134200
In the Entry List you can use the certificate type (general product approval, explosion protection, test certificates, shipbuilding, etc.) as a filter criterion.
Operation of the 3VA1 and 3VA2 molded case circuit breakers is approved in accordance with IEC / EN 60947-1 and IEC / EN 60664-1 for pollution degree 3.
3VA molded case circuit breakers are used at ambient temperatures from -25 °C to +70 °C. Derating (reduction in rated operational current) is required at temperatures above +50 °C. You will find more information on the applicable derating factors in chapter Derating and temperature compensation (Page 489).
The permissible storage temperature in original Siemens packaging lies between -25 °C and +80 °C.
).
3VA molded case circuit breakers including their accessories can also be used in challenging operating environments.
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Harsh conditions of storage, transportation and stationary use
Class E
Vibration resistance and shock resistance
2.5 Standards and guidelines
The molded case circuit breakers have been tested according to the relevant special test procedures defined in IEC / EN 60947-1, Appendix Q for
applications.
This class covers the areas MC3 + CC2 + SC1:
● Ambient temperature
● Humidity
● Vibration environment
● Shock environment
These ambient conditions can be referred to as "Open deck, damp and cold atmosphere without salt spray" or "Difficult, non-marine conditions".
The following standards-related criteria are complied with:
● IEC / EN 60068-2-2 "Bd" and IEC / EN 60068-2-1 "Ab":
Temperature range: -25 °C … +70 °C
● IEC / EN 60068-2-30 "Db"
Humid heat up to +55 °C and air humidity up to 95 %
● IEC / EN 60068-2-6 "Fc"
Vibration test
● IEC / EN 60068-2-27 "Ea"
Shock resistance test
Between the tests of compliance with the standards and at the end of the tests, the usability of the devices is assured with the "Verification of operation characteristics".
3VA molded case circuit breakers are insensitive to vibrations and meet the requirements relating to mechanical and electromechanical vibration strength according to IEC / EN 60068 and the specifications of the shipbuilding societies.
The circuit breakers resist impacts of up to 10 g and are tested to withstand without damage their operating conditions with shock impact according to IEC / EN 60068-2 27 "Ea" with 150 m/s² / 11 ms.
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Installation altitudes
2.5.5

Permissible mounting positions

①
②
③
④
2.5 Standards and guidelines
When 3VA1 and 3VA2 molded case circuit breakers are used at up to 2000 m above sea level, the rated data will not change.
An installation altitude above 2000 m can lead to higher temperatures at the switching devices. The lower density of air can significantly reduce heat dissipation,
making it necessary to decrease rated operational voltage, the rated uninterrupted current and the short-circuit values.
Refer to the table below for the calculation factor for determining the key values:
1)
At maximum ambient temperature +50 °C
2)
Thermal-magnetic trip units only
The permissible mounting positions for 3VA molded case circuit breakers are illustrated below:
Vertical wall mounting Ceiling mounting Floor mounting Laterally rotated wall mounting
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Further mounting positions, and mounting positions with accessories
2.5 Standards and guidelines
The following table shows the possible variations on the mounting positions, as well as mounting positions with accessories:
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2.5.6

Safety clearances

①
②
Minimum clearance between molded case circuit breaker and side walls left / right (uninsulated
earance between two horizontally installed molded case circuit breakers, see tables
2.5 Standards and guidelines
During a short-circuit interruption, high temperatures, ionized gases and high pressures occur in and above the arcing chambers of the molded case circuit breaker.
Safety clearances are required to:
● allow pressure distribution
● prevent fire or damage caused by any diffused ionized gases
● prevent a flashover to grounded parts
● prevent arcing or short-circuit currents to live sections.
The following safety clearances apply to 3VA molded case circuit breakers:
Molded case circuit breaker without accessories or with short terminal cover Molded case circuit breaker with accessories, e.g. phase barrier or long terminal cover
A Minimum clearance between molded case circuit breaker and current paths (uninsulated and
grounded metal), see tables below
B
and grounded metal), see tables below
C Minimum cl
below; applicable to fixed-mounted and plug-in versions (see chapter
(Page 201)) D Minimum clearance between molded case circuit breaker and control cabinet door E Minimum clearance between live parts of connection system and grounded mounting plate
Plug-in and draw-out technology
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connection bars broadened
2.5 Standards and guidelines
Minimum clearance for 3VA1 molded case circuit breakers:
1)
Can be used for connection methods: box terminal, screw-type terminal, internal circular conductor terminal, and
rear terminals
2)
Can be used for connection methods: circular conductor terminal large, front connection bars extended, and front
Minimum clearance for 3VA2 molded case circuit breakers:
1)
Can be used for connection methods: box terminal, screw-type terminal, internal circular conductor terminal, and
rear terminals
2)
Can be used for connection methods: circular conductor terminal large, front connection bars extended, and front
connection bars broadened
O. r. On request
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Note
NOTICE
Damage to the molded case circuit breaker and the system
2.5 Standards and guidelines
In addition to the clearances stated above, any insulating equipment that might be required must also be considered, see chapter Insulating equipment (Page 191).
It must be ensured that the cable or busbar connection does not reduce the air insulation clearance.
Accessory components can increase the width or height of the molded case circuit breaker. In this case the minimum clearances apply from the corresponding sides of the overall molded case circuit breaker/accessory combination.
Depending on the application, larger minimum clearances may be necessary.
Please observe the specifications regarding air and creepage distances in the applicable overriding guidelines (e.g. IEC 61439).
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Safety clearances between molded case circuit breakers
①
②
③
④
⑤
⑥
2.5 Standards and guidelines
No minimum clearance needs to be observed between the molded case circuit breakers on the longitudinal sides (see table above).
The following safety clearances apply to molded case circuit breakers installed directly on top of each other:
x See tables below for minimum clearance
Front connection with cable, direct Front connection with cable lug Front connection with flat busbar Rear connection with plug-in base or busbar terminals Insulation of cable Insulation of busbar
Minimum clearance for 3VA1 molded case circuit breakers:
Minimum clearance for 3VA2 molded case circuit breakers:
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2.5.7

Degrees of protection

2.5.8

Environmental protection

2.5 Standards and guidelines
3VA molded case circuit breakers comply with the following degrees of protection as defined by IEC 60529 and IEC 60947-1, Appendix C:
Degree of protection IP40 is achieved when a 3VA molded case circuit breaker is installed in a switchboard with a door cutout including release (see below). The units can be upgraded to comply with higher degrees of protection up to IP65 by installation of the following components:
● Door mounted rotary operator
● Side wall mounted rotary operator
Maximum door cutout IP40:
Handle and release are freely accessible, the control cabinet door closes flush with the molded case circuit breaker.
The 3VA1 and 3VA2 molded case circuit breakers meet the specifications of the European Environment Guideline 2002 / 95 / EU RoHS directive (Restriction of the use of certain hazardous substances in electrical and electronic equipment). The development and production processes have been devised to have the lowest possible environmental impact.
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2.6
Protection system

2.6 Protection system

This chapter contains an overview of the protection system of 3VA molded case circuit breakers.
The topics discussed in this chapter are listed below:
● Description of functions
● Overload protection (L)
● Short-time delayed short-circuit protection (S)
● Instantaneous short-circuit protection (I)
● Ground-fault protection (G)
● Neutral conductor protection (N)
● ZSI - Zone Selective Interlocking
● Guide to setting the tripping characteristic
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2.6.1

Description of functions

2.6 Protection system
The protection function performed by the molded case circuit breaker in the power distribution network is defined by the choice of trip unit. There are two different types of trip unit, i.e. thermal-magnetic (TMTU) and electronic (ETU):
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2.6 Protection system
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2.6.2

Characteristic curves

Tripping characteristics for thermal-magnetic trip units
Tripping characteristics for electronic trip units
2.6 Protection system
To design a low-voltage switchboard in accordance with the valid rules, the system planner needs to dimension the protection settings of the molded case circuit breakers.
The settings selected for the trip unit of a molded case circuit breaker depend on the type of equipment to be protected, e.g. switchboard and applications.
Tripping characteristics up to a tripping time of ≥ 1 ms are represented graphically. In order to ease the coordination of different protection devices, the current is specified as a multiple of the current setting value and the time is specified in seconds.
Characteristics are displayed graphically in the double-log coordinate system (cf. IEC 60947-2, paragraph 4.7.4 and IEC 60269-1). The current : time ratio is 2 : 1.
Characteristics are displayed graphically in the double-log coordinate system (cf. IEC 60269-1). The current : time ratio is 1 : 1.
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①
⑥
②
⑦ ③
④
⑤
2.6 Protection system
Response threshold of the long-time delayed
protection, thermal
Response threshold of the long-time delayed
protection Delay of the long-time delayed protection L Overload range Response threshold of the short-time delayed
protection I2t characteristic ON/OFF of the short-time
delayed protection
Delay of the short-time delayed protection
Response threshold of the instantaneous
protection
S Short-time delayed short-circuit current
range
I Instantaneous short-circuit current range
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2.6.3

Guide to setting the tripping characteristic

Supplementary conditions
SIMARIS design
2.6 Protection system
The settings selected for the trip unit of a molded case circuit breaker depend on the technical environment (e.g. switchboard and applications) and the type of equipment to be protected. The task of calculating and dimensioning the protection settings in accordance with the valid rules is the responsibility of the system planner.
The Siemens SIMARIS design software tool is a fast, simple and reliable tool for calculating and dimensioning networks in accordance with the valid rules:
For further information about SIMARIS design, please visit:
(http://www.siemens.com/simaris
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Basic rules for setting different trip parameters
Setting the parameters for trip units ETU 5-series and 8-series
2.6 Protection system
ETU 5-series and 8-series are equipped with an LCD.
Parameter settings can be adjusted via this LCD, values are input by means of buttons. The powerconfig software can also be used to input parameter settings. The TD500 test device and the COM800/COM100 breaker data server combined with the COM060 communication module can be used as the software interface.
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2.6.4

Overload protection (L)

Thermal image
Thermal image activated (ON)
Thermal image deactivated (OFF)
2.6 Protection system
The ID letter for overload protection is L (stands for "Long-time delay").
The trip unit is inverse-time delayed and exhibits the following characteristics depending on the trip unit type:
● Bimetal characteristic with thermal-magnetic trip units
2
t characteristic with electronic trip units
● I
The letters I
refer to the current setting value, and tr to the associated time delay.
r
The time delay with the device-specific reference point defines the current-dependent curve shape of the setpoint characteristic. With 3VA molded case circuit breakers, this trip unit reference point corresponds to 6 times the current setting value I
. The following
r
mathematical equation determines the remaining curve of the setpoint characteristic:
2
I
t = constant
The electronic trip units feature a thermal image function that can be deactivated on some electronic trip units.
If the thermal image is activated, the previous thermal history is taken into account. After tripping, the thermal memories of the phases are set to a value corresponding to 85 % of the thermal equivalent of the warmest phase. This setting allows reclosure of the contacts of the molded case circuit breaker. This is followed by a cool-down period according to an exponential function with a time constant T
au
(τ).
The thermal image for ETU 5-series and 8-series can be deactivated to allow use of the TD500 test device for characteristic curve tests. The thermal image must remain activated in normal operation. When the image is deactivated, the thermal prehistory of the circuit breaker, the cables/busbars, other components of the lower-level power distribution system or an end consumer is ignored.
It is the responsibility of the commissioning engineer/operator to provide additional thermal overload protection for the lower-level power distribution system while the thermal image is deactivated.
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2.6.5

Short-time delayed short-circuit protection (S)

2.6.6

Instantaneous short-circuit protection (I)

2.6.7

Ground-fault protection (G)

2.6 Protection system
The ID letter for short-time delayed short-circuit protection is "S" (stands for "Short-time delay"). The S function of the trip unit can be used to implement time-selective short-circuit tripping in low-voltage networks in which multiple molded case circuit breakers are installed in series.
The short-time delayed short-circuit protection function protects phases L1 to L3 and the neutral conductor. The protection function responds if the current in at least one phase exceeds the set tripping current I
The S release operates according to a characteristic with a current-dependent curve I
for the set delay period tsd.
sd
2
t. The electronic trip units ETU 5-series and 8-series can be optionally switched over to a current­independent tripping characteristic.
The ID letter for instantaneous short-circuit protection is "I" (stands for "Instantaneous").
This short-circuit protection function protects phases L1 to L3. The instantaneous short­circuit protection function responds if the instantaneous value equal to the rms of the current in at least one phase exceeds the instantaneous tripping current I
.
i
The ID letter for ground-fault protection is "G" (ground fault).
The G protection detects residual currents between phases and grounded, electrically conductive parts. The ground-fault protection function responds if the ground fault current exceeds the set tripping current I
for the set delay period tg.
g
Ground-fault protection can be implemented as a current-independent and a current­dependent function (I
2
t).
On 4-pole molded case circuit breakers and 3-pole molded case circuit breakers with external current transformer for N conductor, the G protection calculates the vector sum of the currents of the three phases and the neutral conductor. The G release trips the breaker or an alarm is issued via the communication system if the rms value of this vector sum exceeds the set trip value I
for the duration of the set delay tg.
g
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2.6.8

Neutral conductor protection (N)

Note
Neutral conductor protection
Neutral conductor protection and 3VA2 molded case circuit breakers
2.6 Protection system
The ID letter for neutral conductor protection is "N".
The neutral conductor protection system protects the neutral conductor against overloads and short circuits.
The letters I
A neutral conductor with full cross sectional area (distributed neutral conductor of the same size as the phases) is normally protected by the phase protection system and does not require separate protection.
Neutral conductor protection must be implemented in accordance with the standards valid in the country of installation. Possible reasons for implementing neutral conductor overload protection are:
● The neutral conductor has a smaller cross section than the phase conductors.
● Harmonic levels in the installation are expected to be higher than normal.
● A large number of loads, or predominantly single-phase loads, will be connected.
● The neutral conductor will be isolated for functional reasons, e.g. because there are
several voltage sources.
● The neutral conductor will be isolated for safety reasons, e.g. because work is in progress on disconnected units
refer to the current setting value; the associated setting time is identical to tr.
N
The following versions of 3VA2 molded case circuit breaker have neutral conductor protection:
● All 3-pole versions with external current transformer for N conductor
● All 4-pole versions
Oversized neutral conductor protection can be implemented in combination with the electronic trip units ETU 5-series and 8-series. This might be necessary to provide protection against third-order harmonics and multiples thereof.
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Parameters of the neutral conductor protection function
2.6 Protection system
N Neutral conductor protection
1)
At rated operational currents In ≤ 63 A: IN = 40 % … 100 % In
2)
Applies to In > 63 A
3)
Dependent on circuit breaker size and rated operational current
● Tripping current IN:
Adjustable as a proportion of the current setting (I
● Tripping delay:
Corresponds to the delay setting (t
) for overload protection
r
● Tripping current of the short-time delayed short-circuit protection:
Corresponds to the short-time delayed short-circuit protection (I
● Tripping delay:
Corresponds to the delay setting for short-time delayed short-circuit protection (t
● Instantaneous short-circuit protection:
Corresponds to the tripping current (I
) for overload protection
r
)
sd
) for instantaneous short-circuit protection
i
)
sd
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Example of a neutral conductor protection characteristic
①
②
Adjustment of neutral conductor protection settings
2.6 Protection system
Response threshold of the neutral conductor protection Response threshold of the long-time delayed protection
The tripping current IN can be adjusted:
● for ETU 3-series trip units via setting buttons
● for ETU 5-series and 8-series trip units
– via the buttons on the ETU display
– via a PC using powerconfig
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2.6.9

Zone-selective interlocking ZSI

Note Downward compatibility
2.6 Protection system
The microprocessor-controlled, zone-selective interlocking function has been developed in order to control the total breaking time in low-voltage networks with multiple molded case circuit breakers connected in series.
Regardless of the number of series-connected molded case circuit breakers, all short circuits in the network can be cleared within a maximum time period of 50 ms.
The ZSI function of 3VA molded case circuit breakers is compatible with the ZSI functions of Siemens 3VL molded case circuit breakers and 3WL air circuit breakers.
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Description
Operating principle
2.6 Protection system
The diagram below demonstrates the operating principle of zone-selective interlocking:
- - - Communication cable t
A Output, transmits the blocking signal t E Input, receives the blocking signal t
"Virtual" tripping time of I protection
i
Delay time setting of S protection
SD
Delay time of all molded case circuit breakers
ZSI
which detect the short circuit but do not receive a blocking signal when ZSI is activated
The ZSI function acts on the S and G ranges of the tripping characteristic. Currents within the I range (instantaneous short circuit) continue to cause instantaneous tripping.
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Fault 1
Fault 2
Fault 3
Fault 4
2.6 Protection system
If the short-circuit current is sufficiently large, the trip units of molded case circuit breakers Q41, Q33, Q22 and Q11 are activated. Since Q41 clears the fault within t
= 10 ms, none of
i
the other molded case circuit breakers trips even though Q41 has no ZSI and cannot therefore transmit a blocking signal to Q33.
If the short-circuit current is sufficiently large, the trip units of molded case circuit breakers Q32, Q22 and Q11 are activated. As a result of the ZSI function, Q32 temporarily blocks Q22 which in turn temporarily blocks Q11. Depending on the magnitude of the short-circuit current, the fault is cleared either within t
= 10 ms or t
i
= 50 ms.
zsi
Q22 signals short-circuit protection to Q11 with the result that only Q22 trips when delay time t
= 50 ms expires. Without the ZSI function, the fault would not be cleared until tsd = 200 ms
zsi
had expired.
The short circuit is detected only by Q11. Since Q11 does not receive a blocking signal from the downstream molded case circuit breakers, it trips after t function, Q11 would not trip until t
= 300 ms had expired.
sd
= 50 ms. Without the ZSI
zsi
It is especially important to minimize breaking times when short circuits involving very high short-circuit currents occur.
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2.7
Thermal-magnetic trip unit
2.7.1

Thermal trip unit (L)

2.7.2

Magnetic trip unit with short-circuit protection (I)

2.7 Thermal-magnetic trip unit

A thermal-magnetic trip unit consists of a thermal trip unit for protecting against overload, and a magnetic trip unit for protecting against short circuits. Both trip units are series­connected.
The thermal trip unit consists of a temperature-dependent bimetal that heats up as a result of the flow of current. This means the trip unit is current-dependent. The temperature rise in the bimetal strip depends not only on the current magnitude, but also on the ambient temperature of the molded case circuit breaker. All current values specified for thermal­magnetic trip units of 3VA circuit breakers refer to an ambient temperature of +50 ℃.
The magnetic trip unit with short-circuit protection comprises a yoke mounting through which a current path runs, and a flap armature that is kept at a distance from the yoke mounting by a tension spring.
If a short-circuit current flows along the current path, the magnetic field thus generated causes the flap armature to be moved towards the yoke mounting against the opposite force of the tension spring. The tripping time is almost current-independent and instantaneous. The flap armature releases the breaker mechanism and thus opens the switching contacts. Immediately after tripping, the flap armature is moved back to its starting position by the restoring force of the tension spring.
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2.7.3

Application cases and trip unit types

2.7 Thermal-magnetic trip unit
The table below illustrates the applications for which different types of thermal-magnetic trip units can be used:
1)
For 4-pole molded case circuit breakers only, available without protection, 50% (≥ In 100 A) and
100%
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Description
2.8
Electronic trip unit
①
②
③

2.8 Electronic trip unit

An electronic trip unit is based on the following concepts:
● Complete measurement of the current in the phases L1, L2 and L3, with N and currents to ground optional
● Rogowski coil
– Very precise measurement of the current
– Better ground-fault protection because the vectorial sum is more exact
● Evaluation of the current measurement values and constant comparison with the tripping limits
● Tripping by means of a maglatch
Electronic Trip Unit (ETU) Maglatch Current sensor
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2.8.1

Connections

①
Interface for an external current transformer for N conductor
②
Interface for connection of an EFB300 external function box
③
④
Connection for test devices TD300 and TD500
2.8 Electronic trip unit
The connections on the ETU are illustrated in the diagram below:
Interface for connection of an RCD820 residual current device
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2.8.2

Protection functions

2.8 Electronic trip unit
1)
Available in a version with external current transformer for N conductor or 4-pole breaker
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2.8 Electronic trip unit
1)
Available in a version with external current transformer for N conductor or 4-pole breaker
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2.8.3

Operator controls

①
③
⑤
②
④
⑥
2.8 Electronic trip unit
Name of the ETU LED display
The following figure shows the available ETU types of the 3VA2 molded case circuit breakers. You can decide which ETU to install according to the area of application.
Front interface Setting buttons
Pushbuttons LCD
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LED displays
2.8 Electronic trip unit
The following table explains what the LED displays mean:
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Description
ETU 3-series units
Displays on ETU 5-series and 8-series units
2.8 Electronic trip unit
3-series electronic trip units are equipped with setting buttons. A description of the operating principle of the setting buttons and operating instructions can be found in chapter Guide to setting the tripping characteristic (Page 74).
5-series and 8-series electronic trip units have an LCD display. The displayed values are refreshed once per second.
The following table explains what the symbols in the display mean:
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Displays on ETU 5-series and 8-series units
2.8 Electronic trip unit
The following table explains what functions are performed by the buttons next to the display:
The basic structure comprises the following displays:
● Standard display
● Alarm display
● Measured value display
● Parameter display
If no selection is made within an adjustable time period, the standard display will appear.
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2.8 Electronic trip unit
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Description
Standard display
Alarm display
2.8 Electronic trip unit
Active alarms are displayed consecutively in screens AV1 … AV5. If no alarms are active, these screens are concealed.
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Description
Measured value display
2.8 Electronic trip unit
The table below explains the measured value display:
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Parameter display
2.8 Electronic trip unit
The table below explains the parameter display:
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Description
Setting and changing parameters
"Tripped" display
2.8 Electronic trip unit
1. Use the arrow keys to navigate to the correct display.
2. Press the <OK> button.
→ Edit mode is active. Activation is confirmed by display of "pencil" symbol.
3. Use the arrow keys to adjust the parameter setting.
4. Confirm the setting with the <OK> button, or cancel the operation with <ESC>.
→ The setting is accepted with <OK>. The parameter display now appears.
After the ETU has initiated a trip, the "Tripped" display automatically appears:
This screen can be identified by the word "Trip" which is displayed in the top, right-hand corner. The displayed current value shows the current at the moment of tripping.
Press <ESC> to exit the display.
The additional information contained in the "Tripped" display is explained in the table below:
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Diagnostics display
Activation limits
2.8 Electronic trip unit
When a TD500 test device is connected, you can use it to initiate a test. The following screen appears when a TD500 is connected. The bar flashes at a frequency of 0.5 Hz.
The bar travels from left to right while testing is in progress. The test ends with a trip.
The table below shows the activation limits for the ETUs:
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2.8.4

Load acceptance and load shedding - load management

①
⑤
②
⑥
③
⑦
④
Note No trip
2.8 Electronic trip unit
3VA molded case circuit breakers equipped with an ETU 3-series or higher series provide two current thresholds for the purpose of implementing a local load management function. Load shedding is the upper threshold, and load acceptance the lower threshold.
Incoming alarm "load shedding" Outgoing alarm "load shedding" Parameter load shedding 400 A Current in one phase
Parameter load acceptance 100 A Incoming alarm "load acceptance" Outgoing alarm "load acceptance"
Tripping is never initiated as a result of the current value crossing the upper or lower thresholds.
If the current in one phase exceeds the parameter setting for "load shedding", an incoming alarm "load shedding" is generated. Only when the current in all three phases drops below this threshold is an outgoing alarm "load shedding" generated.
The incoming and outgoing alarms can be output via an optional EFB module and transferred via the communication link.
The opposite applies for the load acceptance threshold. If the current in all three phases drops below the parameter setting, an incoming alarm "load acceptance" is generated. If only one of the three currents exceeds the parameter setting, an outgoing alarm "load acceptance" is generated.
To prevent these alarms being generated by brief current peaks and troughs, they can be delayed by the time t
from 1 s to 15 s.
x
3VA molded case circuit breakers
100 Manual, 04/2015, A5E03603177010-02
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