PD IEC/TR 61912-2:2009
Current
The latest, up-to-date edition.
Low-voltage switchgear and controlgear. Over-current protective devices Selectivity under over-current conditions
Hardcopy , PDF
English
13-05-2009
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FOREWORD
INTRODUCTION
1 Scope
2 Normative references
3 Terms, definitions and abbreviated terms
3.1 Alphabetical index of terms
3.2 Terms and definitions
3.3 Abbreviated terms
4 Scope of selectivity requirements
4.1 General
4.2 Motor protection circuit-breaker/Manual motor starter
5 Selectivity determination
5.1 Circuit-breaker as UD
5.1.1 Selectivity between circuit-breakers
5.1.2 Selectivity between a circuit-breaker (UD) and
a fuse to IEC 60269-1 (DD)
5.1.3 CB/CPS - Selectivity between a circuit-breaker
to IEC 60947-2 (UD) and a CPS to IEC 60947-6-2
(DD)
5.1.4 Circuit-breaker/MOR - Selectivity between a
circuit-breaker (UD) and a motor protection
overload relay to IEC 60947-4-1 or
IEC 60947-4-2 (DD)
5.2 Fuse(s) to IEC 60269-1 as UD
5.2.1 Fuse/circuit-breaker - Selectivity between a fuse
to IEC 60269-1 (UD) and a circuit-breaker (DD)
5.2.2 FU/FU - Selectivity between fuses to IEC 60269-1
(UD and DD)
5.2.3 FU/CPS - Selectivity between fuse(s) to IEC 60269-1
(UD) and a CPS to IEC 60947-6-2 (DD)
5.2.4 FU/MOR - Selectivity between fuse(s) to IEC 60269-1
(UD) and a motor overload protection relay to
IEC 60947-4-1 or IEC 60947-4-2 (DD)
6 Residual current devices (RCDs)
6.1 General
6.2 Selectivity - RCD/RCD
6.2.1 Selectivity between RCDs in the case of
earth-leakage current
6.2.2 Selectivity between RCDs in the case of
earth-fault (ground-fault) current
7 Zone Selective Interlocking (ZSI)
7.1 General
7.2 Operating principle
7.3 Example
8 Over-current protection relay (OCR) - Single input energizing
quantity measuring relays with dependent or independent time
Annex A (informative) - Examples of selectivity between
over-current protection devices Examples of the grades
of selectivity applicable to circuit-breakers
Annex B (informative) - Standing loads - Effect of standing
loads on selectivity in the overload zone
Bibliography
Provides an application guide for the determination of selectivity between over-current protective devices of low-voltage switchgear and controlgear, summarises the definitions of the terminology and provides examples of application.
| Committee |
PEL/121/1
|
| DocumentType |
Standard
|
| Pages |
38
|
| PublisherName |
British Standards Institution
|
| Status |
Current
|
IEC 61912-2:2009(E), which serves as an application guide for the determination of selectivity between over-current protective devices of low-voltage switchgear and controlgear, summarises the definitions of the terminology and provides examples of application.
| Standards | Relationship |
| IEC TR 61912-2:2009 | Identical |
| BS 7375:2010 | Distribution of electricity on construction and demolition sites. Code of practice |
| IEC TR 61912-1:2007 | Low-voltage switchgear and controlgear - Overcurrent protective devices - Part 1: Application of short-circuit ratings |
| IEC 60947-6-2:2002+AMD1:2007 CSV | Low-voltage switchgear and controlgear - Part 6-2: Multiple function equipment - Control and protective switching devices (or equipment) (CPS) |
| IEC 60269-4:2009+AMD1:2012+AMD2:2016 CSV | Low-voltage fuses - Part 4: Supplementary requirements forfuse-links for the protection of semiconductor devices |
| IEC TR 62350:2006 | Guidance for the correct use of residual current-operated protective devices (RCDs) for household and similar use |
| IEC 60947-4-1:2009+AMD1:2012 CSV | Low-voltage switchgear and controlgear - Part 4-1: Contactors and motor-starters - Electromechanical contactors and motor-starters |
| IEC 60050-441:1984 | International Electrotechnical Vocabulary (IEV) - Part 441: Switchgear, controlgear and fuses |
| IEC 60269-2:2013+AMD1:2016 CSV | Low-voltage fuses - Part 2: Supplementary requirements for fuses for use by authorized persons (fuses mainly for industrial application) - Examples of standardized systems of fuses A to K |
| IEC 61008-1:2010+AMD1:2012+AMD2:2013 CSV | Residual current operated circuit-breakers without integral overcurrent protection for household and similar uses (RCCBs) - Part1: General rules |
| IEC 60269-1:2006+AMD1:2009+AMD2:2014 CSV | Low-voltage fuses - Part 1: General requirements |
| IEC 60050-442:1998 | International Electrotechnical Vocabulary (IEV) - Part 442: Electrical accessories |
| IEC 61009-1:2010+AMD1:2012+AMD2:2013 CSV | Residual current operated circuit-breakers with integral overcurrentprotection for household and similar uses (RCBOs) - Part 1: General rules |
| IEC 60269-3:2010+AMD1:2013 CSV | Low-voltage fuses - Part 3: Supplementary requirements for fuses foruse by unskilled persons (fuses mainly for household or similar applications) - Examples of standardized systems of fuses A to F |
| IEC 60947-1:2007+AMD1:2010+AMD2:2014 CSV | Low-voltage switchgear and controlgear - Part 1: General rules |
| IEC 60947-4-2:2011 | Low-voltage switchgear and controlgear - Part 4-2: Contactors and motor-starters - AC semiconductor motor controllers and starters |
| IEC TR 61818:2003 | Application guide for low-voltage fuses |
| IEC 60898-1:2015 | Electrical accessories - Circuit-breakers for overcurrent protection for household and similar installations - Part 1: Circuit-breakers for a.c. operation |
| IEC 60050-826:2004 | International Electrotechnical Vocabulary (IEV) - Part 826: Electrical installations |
| IEC 60947-2:2016 | Low-voltage switchgear and controlgear - Part 2: Circuit-breakers |
| IEC 60050-448:1995 | International Electrotechnical Vocabulary (IEV) - Part 448: Power system protection |
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