1、September 2007DEUTSCHE NORM English price group 15No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 27.060.30!$ID“138253
2、3www.din.deDDIN EN 12953-9Shell boilers Part 9: Requirements for limiting devices of the boiler and accessoriesEnglish version of DIN EN 12953-9:2007-09Growasserraumkessel Teil 9: Anforderungen an Begrenzungseinrichtungen an Kessel und ZubehrEnglische Fassung DIN EN 12953-9:2007-09www.beuth.deDocume
3、nt comprises 39 pages 11.07DIN EN 12953-9:2007-09 2 National foreword This standard has been prepared by Technical Committee CEN/TC 269 “Shell and water-tube boilers” (Secretariat: DIN, Germany). The responsible German body involved in its preparation was the Normenausschuss Rohrleitungen und Dampfk
4、esselanlagen (Pipelines and Pressure Vessels Standards Committee), Technical Committee NA 082-00-18 AA Dampfkesselanlagen. EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 12953-9July 2007ICS 27.060.30English VersionShell boilers - Part 9: Requirements for limiting devices of theboiler and accessor
5、iesChaudires tubes de fume - Partie 9: Exigences pourles dispositifs de limitation de la chaudire et de sesaccessoiresGrowasserraumkessel - Teil 9: Anforderungen anBegrenzungseinrichtungen an Kessel und ZubehrThis European Standard was approved by CEN on 26 May 2007.CEN members are bound to comply w
6、ith the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Ce
7、ntre or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial
8、 versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia,
9、 Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national
10、Members.Ref. No. EN 12953-9:2007: EEN 12953-9:2007 (E) 2 Contents Page Foreword 4 1 Scope 6 2 Normative references 6 3 Terms and definitions . 7 4 Requirements for limiter . 9 4.1 General 9 4.2 Materials and design . 9 4.3 Electrical equipment 10 4.4 Fault assessment. 10 4.5 Marking . 12 5 Special r
11、equirements for water level limiters .14 5.1 Components. 14 5.2 Design . 14 5.3 Floating devices. 15 5.4 Level electrode devices 15 5.5 Examination of functional capability . 16 5.6 Fault detection . 19 6 Special requirements for pressure limiters 19 6.1 Components. 19 6.2 Additional fault assessmen
12、t requirements .19 6.3 Design . 19 6.4 Electrical equipment 20 6.5 Examination of functional capability . 20 6.6 Fault detection . 22 7 Special requirements for temperature limiters. 22 7.1 Components. 22 7.2 Design . 22 7.3 Electrical equipment 24 7.4 Examination of functional capability . 24 8 Spe
13、cial requirements for flow limiters. 25 8.1 Components. 25 8.2 Design . 25 8.3 Electrical equipment 25 8.4 Examination of functional capability . 25 Annex A (informative) Limiting device 26 Annex B (informative) Example of an examination plan . 27 Annex C (informative) Marking of limiters 29 Annex D
14、 (normative) Immunity against electrical and electromagnetic influences Requirements and testing. 32 D.1 General 32 D.2 Immunity against mains voltage variations 32 D.3 Immunity against short-time voltage interruptions and reductions. 32 D.4 Immunity against mains frequency changes 33 D.5 Immunity a
15、gainst electrostatic discharge (ESD) 33 D.6 Immunity against fast transient disturbance variables (burst). 33 D.7 Immunity against surges 34 D.8 Immunity against high-frequency electromagnetic fields. 34 D.9 Immunity against conducted disturbances induced by high frequency fields. 35 D.10 Immunity a
16、gainst power frequency magnetic fields 35 EN 12953-9:2007 (E) 3 Annex ZA (informative) Relationship between this European Standard and the Essential Requirements of EU Directive 97/23/EC 36 Bibliography 37 EN 12953-9:2007 (E) 4 Foreword This document (EN 12953-9:2007) has been prepared by Technical
17、Committee CEN/TC 269 “Shell and water-tube boilers”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by January 2008 and conflicting national standards shall
18、be withdrawn at the latest by January 2008. This document has been prepared under a mandate given to CEN by the European Commission and the European Free Trade Association, and supports essential requirements of EU Directive(s). For relationship with EU Directive(s), see informative Annex ZA, which
19、is an integral part of this document. The European Standard EN 12953 concerning shell boilers consists of the following Parts: Part 1: General Part 2: Materials for pressure parts of boilers and accessories Part 3: Design and calculation for pressure parts Part 4: Workmanship and construction of pre
20、ssure parts of the boiler Part 5: Inspection during construction, documentation and marking of pressure parts of the boiler Part 6: Requirements for equipment for the boiler Part 7: Requirements for firing systems for liquid and gaseous fuels for the boiler Part 8: Requirements for safeguards agains
21、t excessive pressure Part 9: Requirements for limiting devices of the boiler and accessories Part 10: Requirements for feedwater and boiler water quality Part 11: Acceptance tests Part 12: Requirements for grate firing systems for solid fuels for the boiler Part 13: Operating instructions CR 12953 P
22、art 14: Guideline for the involvement of an inspection body independent of the manufacturer. Although these Parts may be obtained separately, it should be recognised that the Parts are interdependent. As such, the design and manufacture of shell boilers requires the application of more than one Part
23、 in order for the requirements of the European Standard to be satisfactorily fulfilled. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Republic
24、, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 12953-9:2007 (E) 5 Introduction The types of limiters wh
25、ich shall be fitted to boilers are specified in EN 12953-6 and the design of the safety systems are specified in EN 50156-1. A limiter (or limiting device) is one element of a shell boiler safety system. It comprises a sensor and monitoring elements to achieve the desired level of reliability. In or
26、der to provide the necessary safety function, for example, to cut off the heat supply to the boiler in the event of a low water fault, the limiter is connected to other elements in the safety system such as actuators and safety logic circuits. EN 12953-9:2007 (E) 6 1 Scope This European Standard spe
27、cifies requirements for limiters (or limiting devices) which are incorporated into safety systems for shell boilers as defined in EN 12953-1. A limiter (or limiting device) can be either: a safety accessory as defined in the Pressure Equipment Directive, Article 1, clause 2.1.3, and needs to include
28、 the safety logic and final actuator, or one element of a safety system, for example, a self-monitoring water level sensor used as part of a safety accessory as defined in the Pressure Equipment Directive, Article 1, clause 2.1.3. The overall boiler protection function needs to be provided in associ
29、ation with additional safety logic (where appropriate) and a final actuator. The design requirements and examination of functional capability for the limiters are covered in this European Standard. For an explanation of the extent of the limiter (or limiting device) see Figure A.1. 2 Normative refer
30、ences The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 298:2003, Automatic gas burner control s
31、ystems for gas burners and gas burning appliances with or without fans EN 50156-1:2004, Electrical equipment for furnaces and ancillary equipment Part 1: Requirements for application design and installation EN 60529:1991, Degrees of protection provided by enclosures (IP code) (IEC 60529:1989) EN 606
32、64-1:2003, Insulation coordination for equipment within low-voltage systems Part 1: Principles, requirements and tests (IEC 60664-1:1992 + A1:2000 + A2:2002) EN 60730-1:2000, Automatic electrical controls for household and similar use Part 1: General requirements (IEC 60730-1:1999, modified) EN 6100
33、0-4-2:1995, Electromagnetic compatibility (EMC) Part 4: Testing and measurement techniques Section 2: Electrostatic discharge immunity test Basic EMC publication (IEC 61000-4-2:1995) EN 61000-4-3:2006, Electromagnetic compatibility (EMC) Part 4-3: Testing and measurement techniques Radiated, radio-f
34、requency, electromagnetic field immunity test (IEC 61000-4-3:2006) EN 61000-4-4:2004, Electromagnetic compatibility (EMC) Part 4-4: Testing and measurement techniques Electrical fast transient/burst immunity test (IEC 61000-4-4:2004) EN 61000-4-5:2006, Electromagnetic compatibility (EMC) Part 4: Tes
35、ting and measurement techniques Section 5: Surge immunity test (IEC 61000-4-5:2005) EN 61000-4-6:1996, Electromagnetic compatibility (EMC) Part 4: Testing and measurement techniques Section 6: Immunity to conducted disturbances, induced by radio-frequency fields (IEC 61000-4-6:1996) EN 61000-4-8:199
36、3, Electromagnetic compatibility (EMC) Part 4: Testing and measurement techniques Section 8: Power frequency magnetic field immunity test; basic EMC publication (IEC 61000-4-8:1993) EN 12953-9:2007 (E) 7 EN 61000-4-11:2004, Electromagnetic compatibility (EMC) Part 4-11: Testing and measurement techn
37、iques Voltage dips, short interruptions and voltage variations immunity tests (IEC 61000-4-11:2004) EN 61000-6-2:2005, Electromagnetic compatibility (EMC) Part 6-2: Generic standards Immunity for industrial environments (IEC 61000-6-2:2005) EN 61508-3:2001, Functional safety of electrical/electronic
38、/programmable electronic safety-related systems Part 3: Software requirements (IEC 61508-3:1998 + Corrigendum 1999) 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 limiter limiting device that, on reaching a fixed value (e.g. pressure, temper
39、ature, flow, water level) is used to interrupt and lock-out the energy supply NOTE Limiting device comprises: a measuring or detection function and an activation function for correction, or shutdown, or shutdown and lockout, and which is used to carry out safety related functions as defined in the P
40、ED, on its own or as part of a safety (protective) system (e.g. sensors, limiters) (see also Figure 1). If this is achieved by multi channel systems, then all items or limiters for safety purposes are included within the safety (protective) system Figure 1 Protective devices and safety accessories a
41、ccording to Directive 97/23/EC (PED) 3.2 actuating element component which produces changes in other electrical circuits or volume flows (e.g. fuel, air) as a result of the effect of changes in signal NOTE For example, a gas shut off valve is not an actuating element. 3.3 fail-safe limiter is fail-s
42、afe if it possesses the capability of remaining in a safe condition or transferring immediately to another safe condition in the event of certain faults occurring EN 12953-9:2007 (E) 8 3.4 self-monitoring regular and automatic determination that all chosen components of a safety system are capable o
43、f functioning as required 3.5 redundancy provision of more than one device or system which, in the event of a fault, will still be provided by the necessary facilities 3.6 diversity provision of different means of performing the required function, e.g. other physical principles or other ways of solv
44、ing the same problem 3.7 complex electronics assemblies which use electronic components with more than one functional output 3.8 safety shut-down process which is effected immediately following the detection of a fault within the limiter or caused by exceeding the threshold of the process value limi
45、t resulting in a defined state with deactivated terminals of the safety output(s) 3.9 lock-out safety shut-down condition of the limiter, such that a restart can only be accomplished by a manual reset of the limiter or by a manual reset of the safety logic and by no other means NOTE This will be ach
46、ieved by a competent operator taking account of the physical situation 3.10 sensor transducer which, on reaching a defined limit value, outputs a signal and/or cuts out and only reverses the output signal in the event of a specific change in the performance quantity (e.g. pressure, temperature, flow
47、, level) NOTE Sensors are used for signalling or for triggering control processes EN 12953-9:2007 (E) 9 4 Requirements for limiter 4.1 General 4.1.1 The requirements set out below have been established to ensure uniform assessment of different devices. A limiter shall be such that a single fault in
48、any related part shall not lead to a loss of the safety function. This shall be achieved by fault avoidance techniques such as self-monitoring with redundancy, diversity or a combination of these methods. Fault assessment for the electrical components shall be in accordance with 4.4. The fault asses
49、sment chart, see Figure 2 shall also be applied for faults in hydraulic, pneumatic and mechanical components. NOTE The various elements of limiters are given in Annex A. 4.1.2 Limiters shall function independently of each other and of controls unless their safety function cannot be affected by other such functions. Manual resetting can be realised as a part of the limiter or as a part of the safety logic. Instructions shall be delivered together with the limiter including necessary precautions
