SIST EN 161:2011+A2:2013

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Automatische Absperrventile für Gasbrenner und GasgeräteRobinets automatiques de sectionnement pour brûleurs à gaz et appareils à gazAutomatic shut-off valves for gas burners and gas appliances27.060.20Plinski gorilnikiGas fuel burners23.060.10Zapirni ventili (kroglasti)Globe valvesICS:Ta slovenski standard je istoveten z:EN 161:2011+A2:2012SIST EN 161:2011+A2:2013en,fr,de01-januar-2013SIST EN 161:2011+A2:2013SLOVENSKI
STANDARDSIST EN 161:20111DGRPHãþD



SIST EN 161:2011+A2:2013



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 161:2011+A2
August 2012 ICS 23.060.10 Supersedes EN 161:2011English Version
Automatic shut-off valves for gas burners and gas appliances
Robinets automatiques de sectionnement pour brûleurs à gaz et appareils à gaz
Automatische Absperrventile für Gasbrenner und Gasgeräte This European Standard was approved by CEN on 20 February 2011 and includes Amendment 2 approved by CEN on 10 June 2012.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre:
Avenue Marnix 17,
B-1000 Brussels © 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 161:2011+A2:2012: ESIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 2 Contents Page Foreword .31Scope .52Normative references .53Terms and definitions .64Classification .75Units of measurement and test conditions .86Construction requirements .87Performance . 138EMC/Electrical requirements . 219Marking, installation and operating instructions . 23Annex A (informative)
Gas connections in common use in the various countries . 25Annex B (informative)
Leak-tightness test – volumetric method . 26Annex C (informative)
Leak-tightness test – pressure loss method . 27Annex D (normative)
Conversion of pressure loss into leakage rate . 28Annex E (normative)
Electrical/electronic component fault modes . 29Annex F (normative)
Additional requirements for safety accessories and pressure accessories as defined in EU Directive 97/23/EC . 30Annex G (normative)
Materials for pressurized parts . 31Annex H (informative)
Additional materials for pressurized parts . 32Annex I (normative)
Requirements for controls used in DC supplied gas burners and gas burning appliances . 33Annex ZA (informative)
Relationship between this European Standard and the Essential Requirements of EU Directive 2009/142/EC relating to appliances burning gaseous fuels . 34Bibliography . 36 Tables Table 1 — Test pressure . 13Table 2 — Sealing force requirements . 17Table 3 — Operating cycles . 20Table 4 — Operating cycles for automatic shut-off valves for cookers according to EN 30-1-4:2002, 5.3.7.1 . 20Table ZA.1 — Correspondence between this European Standard and Directive 2009/142/EC relating to appliances burning gaseous fuels . 34 SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 3 Foreword This document (EN 161:2011+A2:2012) has been prepared by Technical Committee CEN/TC 58 “Safety and control devices for burners and appliances burning gaseous or liquid fuels”, the secretariat of which is held by BSI. 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 February 2013, and conflicting national standards shall be withdrawn at the latest by February 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. This document supersedes #EN 161:2011.$ #This document includes Amendment 2 approved by CEN on 10 June 2012.$ The start and finish of text introduced or altered by amendment is indicated in the text by tags #$. This document is intended to be used in conjunction with #EN 13611:2007+A2:2011$. This document refers to clauses of #EN 13611:2007+A2:2011$ or adapts clauses by stating “with the following modification”, “with the following addition”, “is replaced by the following” or "is not applicable" in the corresponding clause. This European Standard adds clauses or sub-clauses to the structure of #EN 13611:2007+A2:2011$ which are particular to this European Standard i.e. sub-clauses or annexes, which are additional to those in #EN 13611:2007+A2:2011$, are numbered starting from 101 or are designated as Annex AA, BB, CC etc. It should be noted that these clauses and sub-clauses are not indicated as an addition. #At the time of publication of this document, Amendment 1 was still at the draft stage. Therefore, there will be no Amendment 1 for this project. The next amendment to be published will be Amendment 3, which will incorporate the changes of the original Amendment 1 and this document.$ It should be noted that the following significant editorial changes compared to the previous edition have been incorporated in this European Standard:
a) alignment to #EN 13611:2007+A2:2011$; b) normative references: ISO 4400 and ISO 6952 are changed to EN 175301-803; c) terms and definitions are aligned to #EN 13611:2007+A2:2011$; d) sub-clause 6.101 has been moved to sub-clause 8.11.102; e) installation and operating instructions are integrated in one sub-clause; f) changes in Annex ZA regarding 1.2, 1.2.2, 1.2.3, 1.3, 3.1.1, 3.3, 3.6, 3.7, 3.8, 3.11, 3.12, 3.2.1 and in addition Annex II and III were deleted.
SIL classification according to EN 61508 cannot be claimed based upon compliance with this standard. Valves with SIL classification do not meet automatically the requirements of this standard. According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 4 Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 5
1 Scope This European Standard specifies the safety, construction and performance requirements for automatic shut-off valves for use with gas burners, gas appliances and similar use, hereafter referred to as ‘valves’.
This European Standard is applicable to valves with declared maximum inlet pressures up to and including 500 kPa (5 bar) of nominal connection sizes up to and including DN 250 for use with one or more fuel gases in accordance with EN 437. This European Standard is applicable to electrically operated valves and to valves actuated by fluids where the control valves for these fluids are actuated electrically, but not to any external electrical devices for switching the control signal or actuating energy. An assessment method for valve designs is given by this European Standard. This European Standard is also applicable to valves where the flow rate is controlled by external electrical signals, either in discrete steps or proportional to the applied signal. This European Standard is also applicable to valves fitted with closed position indicator switches. NOTE Provisions for final product inspection and testing by the manufacturer are not specified. 2 Normative references 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 30 (all parts), Domestic cooking appliances burning gas EN 298, Automatic gas burner control systems for gas burners and gas burning appliances with or without fans #EN 13611:2007+A2:2011$, Safety and control devices for gas burners and gas burning appliances — General requirements EN 13906-1, Cylindrical helical springs made from round wire and bar — Calculation and design — Part 1: Compression springs EN 13906-2, Cylindrical helical springs made from round wire and bar — Calculation and design — Part 2: Extension springs EN 60529, Degrees of protection provided by enclosures (IP code) (IEC 60529:1989) EN 60730-1:2000, Automatic electrical controls for household and similar use — Part 1: General requirements (IEC 60730-1:1999, modified) EN 61058-1, Switches for appliances — Part 1: General requirements (IEC 61058-1:2000 modified + A1:2001 (Equivalent) EN 175301-803, Detail Specification: Rectangular connectors — Flat contacts, 0,8 mm
thickness, locking screw not detachable
SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 6 3 Terms and definitions For the purposes of this document, the terms and definitions given in #EN 13611:2007+A2:2011$ and the following apply. 3.101 automatic shut-off valve valve which opens when energized and closes automatically when de-energized 3.102 actuating mechanism part of the valve which moves the closure member 3.103 valve with step control valve which controls the flow rate in steps 3.104 valve with modulating control valve which controls the flow rate continuously between two limits in response to external electrical signals 3.105 closed position indicator switch switch fitted to a valve which indicates when the closure member is in the closed position 3.106 actuating energy required energy for the actuating mechanism to move the closure member to the open position NOTE The actuating energy can have an external source (electrical, pneumatic or hydraulic) and can be transformed inside the valve. 3.107 opening force force required to move the closure member to the open position 3.108 closing force force available to close the valve, independent of any force provided by fuel gas pressure 3.109 sealing force force acting on the valve seat when the closure member is in the closed position, independent of any force provided by fuel gas pressure 3.110 frictional force largest force required to move the actuating mechanism and the closure member from the open position to the closed position with the closure spring removed, independent of any force provided by fuel gas pressure 3.111 actuating pressure hydraulic or pneumatic pressure supplied to the actuating mechanism of the valve 3.112 opening time time interval between energizing the valve and the attainment of the maximum or other defined flow rate SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 7 3.113 closing time time interval between de-energizing the valve and the closure member attaining the closed position 3.114 delay time time interval between energizing the valve and the start of flow 3.115 control valve valve which controls the fluid (e. g. compressed air) supplied to the actuating mechanism 3.116 rated voltage voltage declared by the manufacturer at which the valve may be operated 3.117 rated current current declared by the manufacturer at which the valve may be operated 3.118 balanced valve valve with a balanced closure member where the inlet pressure acts on the closure member in the opening and closing direction NOTE The closure member may close more than one opening. 4 Classification 4.1 Classes of control #EN 13611:2007+A2:2011$ is replaced by the following:  Class A, B and C valves Valves where the sealing force is not decreased by the gas inlet pressure. They are classified A, B or C according to the sealing force requirements of 7.105. Balanced valves according to this standard are class A valves.  Class D valves Valves which are not subject for requirements for the sealing force and fixed closing time. NOTE Class D valves are intended to be used for control functions only.  Class J valves Disc-on-seat valves where the sealing force is not decreased by the gas inlet pressure and which meet the requirements of 7.105. 4.2 Groups of control Shall be according to #EN 13611:2007+A2:2011$, 4.2. SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 8 4.3 Classes of control functions Shall be according to #EN 13611:2007+A2:2011$, 4.3. 5 Units of measurement and test conditions Shall be according to #EN 13611:2007+A2:2011$, Clause 5.
6 Construction requirements 6.1 General Shall be according to #EN 13611:2007+A2:2011$, 6.1. 6.2 Mechanical parts of the control 6.2.1 Appearance Shall be according to #EN 13611:2007+A2:2011$, 6.2.1. 6.2.2 Holes Shall be according to #EN 13611:2007+A2:2011$, 6.2.2. 6.2.3 Breather holes Shall be according to #EN 13611:2007+A2:2011$, 6.2.3. 6.2.4 Test for leakage of breather holes Shall be according to #EN 13611:2007+A2:2011$, 6.2.4. 6.2.5 Screwed fastenings Shall be according to #EN 13611:2007+A2:2011$, 6.2.5. 6.2.6 Jointing Shall be according to #EN 13611:2007+A2:2011$, 6.2.6. 6.2.7 Moving parts Shall be according to #EN 13611:2007+A2:2011$, 6.2.7. 6.2.8 Sealing caps Shall be according to #EN 13611:2007+A2:2011$, 6.2.8. 6.2.9 Dismantling and reassembly Shall be according to #EN 13611:2007+A2:2011$, 6.2.9. SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 9 6.2.101 Design There shall be no exposed shafts or operating levers which could adversely affect the ability of valves to close. 6.2.102 Closed position indicator switch Closed position indicator switches, where fitted, shall not impair the correct operation of valves. Adjusters shall be sealed to indicate interference. Any drift of the switch and actuating mechanism from its setting shall not impair correct valve operation. 6.2.103 Valve with modulating control Flow rates of valves with modulating control shall be adjustable over the full range declared by the manufacturer. If the adjustment of one flow rate affects the setting of any other flow rate, this shall be clearly indicated in the manufacturer's instructions for setting up. The setting of any flow rate shall require the use of mechanical or electrical tools and shall be designed to discourage unauthorized adjustment. NOTE For air-gas ratio controls see EN 12067-1 and -2. 6.2.104 Controls assembled to a valve Other controls assembled to a valve shall not interfere with its shut-off function. 6.2.105 Balanced valves # 6.2.105.1 Requirement The closure member of a balanced valve shall have a resulting force in the closing direction where the sealing force is not decreased by the gas inlet pressure. For a balanced valve with one port a resulting force in the closing direction shall remain, if the balancing force is removed, and the closure member shall have the same closing direction as the flow direction through the valve.$ 6.2.106 Closing and sealing 6.2.106.1 Closing and/or sealing by means of springs If springs are used for closing and/or sealing the valve, they shall be designed according to EN 13906-1 or EN 13906-2 for static and dynamic loading. 6.2.106.2 Other means for closing and/or sealing
6.2.106.2.1 General This clause defines a method for the assessment of other means for closing and sealing in automatic shut-off valves. By this clause the term “class of control function A, B or C” is not related to the sealing force classes but to the class of control function as described in 4.3. Sealing force of valves shall be classified according to 4.1. The basic risks of fire and explosion in a gas appliance as a result of uncontrolled gas flow requires a control function class C system for the gas shut-off function. This is based on a comparison, made between automatic SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 10 burner controller and gas shut-off function, the class of control function of each of them being considered equal. Although this European Standard is not based on a fault assessment approach as specified in #EN 13611:2007+A2:2011$, 6.6, the combination of two automatic shut-off valves is considered equal to a control function class C. This assumption is based on the construction and performance requirements of this European Standard. 6.2.106.2.2 New designs for closing and/or sealing New designs for closing and/or sealing shall fulfil at least the requirements of a control function class B. In all cases the gas shut-off function shall be a control function class C. NOTE For further information see EN 14459. During the testing, the valve shall fulfil the performance requirements of Clause 7. New designs may consist of a combination of closure members, electronic controller, sensing elements, actuators, lockout and reset. The manufacturer shall declare the other means for closing and/or sealing. For the assessment of the new design the requirements of this European Standard shall be used in combination with #EN 13611:2007+A2:2011$, 6.6. If this leads to aspects that are not described in this European Standard, the manufacturer shall supply a failure mode analysis on the new design. This analysis shall describe the specific failure modes for the type of technology used in relation to the following basic safety requirements: a) closing function at power interruption; b) leak tightness; c) sealing force (ability to withstand backpressure, to be checked by testing or calculation); d) closing force > friction force; e) closing time including the influence to the Burner Control (EN 298); f) no uncontrolled opening of the automatic shut-off valve. As a result of this failure mode analysis, additional constructional requirements shall be fulfilled and/or additional faults compared to #EN 13611:2007+A2:2011$, Annex E shall be included into the fault assessment. The outcome of the analysis shall provide a set of conditions under which the new design can be used in an automatic shut-off valve. These conditions involve construction requirements, safety requirements, performance requirements and test methods. The fault reaction time shall be declared by the manufacturer. Failure of mechanical parts adversely affecting the performance requirements of this European Standard is considered as an abnormal situation and can therefore be considered as a first fault according to the test method in #EN 13611:2007+A2:2011$, 6.6. However, if mechanical parts are designed according to the constructional requirements of Clause 6 of this European Standard, failure of these parts is not considered. SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 11 ####6.2.107 Additional requirements for shut-off function 6.2.107.1 Diaphragms that assist the shut-off function Shut-off functions using a diaphragm to apply (part of) the closing force to the closure member shall be designed in such a way that, when the diaphragm is damaged, the closure member closes and the maximum internal leakage rate of the valve is limited to 1 dm³/h. Conformity shall be verified by the method given in 6.2.107.2. 6.2.107.2 Leakage test Remove or rupture the part(s) assisting the shut-off function. De-energize the valve. Measure the internal leakage rate of the valve according to 7.3.$ 6.3 Materials 6.3.1 General material requirements Shall be according to #EN 13611:2007+A2:2011$, 6.3.1. 6.3.2 Housing Shall be according to #EN 13611:2007+A2:2011$, 6.3.2. 6.3.3 Test for leakage of housing after removal of non-metallic parts Shall be according to #EN 13611:2007+A2:2011$, 6.3.3. 6.3.4 Zinc alloys Shall be according to #EN 13611:2007+A2:2011$, 6.3.4. 6.3.5 Springs providing closing and/or sealing force Shall be according to #EN 13611:2007+A2:2011$, 6.3.5. 6.3.6 Resistance to corrosion and surface protection Shall be according to #EN 13611:2007+A2:2011$, 6.3.6. 6.3.7 Impregnation Shall be according to #EN 13611:2007+A2:2011$, 6.3.7. 6.3.8 Seals for glands for moving parts Shall be according to #EN 13611:2007+A2:2011$, 6.3.8. 6.3.101 Closure members Closure members of valves above DN 25 shall either have a mechanical support (e. g. metallic) to withstand the sealing force or shall be made of metal. This requirement also applies to: SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 12  all valves with a maximum inlet pressure above 15 kPa (150 mbar);  parts transmitting the closing force. The strength of the connection between closure members of a balanced valve shall be at least five multiplied by the maximum inlet pressure multiplied by the total opening area of the closure members. 6.4 Gas connections 6.4.1 Making connections Shall be according to #EN 13611:2007+A2:2011$, 6.4.1. 6.4.2 Connection sizes Shall be according to #EN 13611:2007+A2:2011$, 6.4.2. 6.4.3 Threads Shall be according to #EN 13611:2007+A2:2011$, 6.4.3. 6.4.4 Union joints Shall be according to #EN 13611:2007+A2:2011$, 6.4.4. 6.4.5 Flanges Shall be according to #EN 13611:2007+A2:2011$, 6.4.5. 6.4.6 Compression fittings Shall be according to #EN 13611:2007+A2:2011$, 6.4.6. 6.4.7 Nipples for pressure test Shall be according to #EN 13611:2007+A2:2011$, 6.4.7 with the following addition: Nipples for pressure test conforming to these requirements shall be used only up to and including 500 mbar. 6.4.8 Strainers Shall be according to #EN 13611:2007+A2:2011$, 6.4.8 with the following addition: Where an inlet strainer is fitted to class A, B, C, and D valves, the maximum strainer hole dimension shall not exceed 1,5 mm and it shall prevent the passage of a 1 mm diameter pin gauge. Class J valves shall incorporate an inlet strainer. The maximum strainer hole dimension shall not exceed 0,28 mm and it shall prevent the passage of a 0,2 mm diameter pin gauge. Strainers fitted to valves of DN 25 and above shall be accessible for cleaning or replacement without removing the valve body by dismantling threaded or welded pipework. 6.5 Electronic parts of valves Shall be according to #EN 13611:2007+A2:2011$, 6.5. SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 13 6.6 Protection against internal faults for the purpose of functional safety Shall be according to #EN 13611:2007+A2:2011$, 6.6. 6.101 Pneumatic and hydraulic actuating mechanisms Pneumatic or hydraulic actuated valves shall be provided with protection to ensure that the blockage of an orifice in the control system does not adversely affect the performance requirements as given in Clause 7. 7 Performance 7.1 General Shall be according to #EN 13611:2007+A2:2011$, 7.1 with the following addition: Valves shall close automatically when de-energized or in the absence of actuating energy. Valves with DC supplies shall operate correctly from the minimum rated voltage to the maximum rated voltage, as declared by the manufacturer. For DC supplies type A, B, and C according to #EN 13611:2007+A2:2011$, Annex I.1 a tolerance of 20 % to the minimum and the maximum rated voltage applies. For DC supplies of other types the tolerance shall be declared by the manufacturer. The electrical control valve of pneumatic or hydraulic actuating mechanisms shall also meet these requirements. The closing of pneumatically or hydraulically actuated valves shall be ensured over the range from 85 % to 110 % of the actuating pressure or pressure range declared by the manufacturer. Aspects coming from new designs for closing and/or sealing according to 6.2.106.2.2 shall be taken as part of the performance requirements, as specified in Clause 7. 7.2 Leak-tightness Shall be according to #EN 13611:2007+A2:2011$, 7.2 with the following addition: Balanced valves shall be leak-tight when tested with rates given in Table 1. Table 1 — Test pressure Inlet pressure Test pressure p in flow direction kPa Maximum leakage rate
0 Pa ≤ p ≤ 50 kPa 2 × pmax For internal leak-tightness see values in #EN 13611:2007+A2:2011$, Table 2 50 kPa < p ≤ 500 kPa p = pmax x [ 2 – ( pmax – 50)/900 ]
SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 14 7.3 Test for leak-tightness 7.3.1 General Shall be according to #EN 13611:2007+A2:2011$, 7.3.1. 7.3.2 External leak-tightness Shall be according to #EN 13611:2007+A2:2011$, 7.3.2. 7.3.3 Internal leak-tightness Shall be according to #EN 13611:2007+A2:2011$, 7.3.3 with the following addition: For balanced valves pressurize the inlet to test pressures given in 7.2 and measure the leakage rate. 7.4 Torsion and bending Shall be according to #EN 13611:2007+A2:2011$, 7.4. 7.5 Torsion and bending tests Shall be according to #EN 13611:2007+A2:2011$, 7.5. 7.6 Rated flow rate Shall be according to #EN 13611:2007+A2:2011$, 7.6 with the following addition: 7.6.101 Valves with modulating control Where the manufacturer declares opening and closing characteristics for valves with modulating control, these shall be within ±10 % of the manufacturer’s declared value. 7.6.102 Valves with step control For valves with step control, where applicable, the manufacturer shall declare the maximum flow rate for each step as a percentage of the fully open flow rate. It shall not be possible to adjust the maximum flow rate for each step in excess of 1,1 times the declared value when tested to 7.7. 7.6.103 Valves with electrical control When the flow rate changes in response to external electrical signals, it shall not, when tested to 7.7, overshoot in either direction while attaining the new flow rate by more than 20 % of the flow rate at that particular set point, or as declared by the manufacturer. 7.7 Test for rated flow rate 7.7.1 Apparatus Shall be according to #EN 13611:2007+A2:2011$, 7.7.1. 7.7.2 Test procedure Shall be according to #EN 13611:2007+A2:2011$, 7.7.2 with the following addition: SIST EN 161:2011+A2:2013



EN 161:2011+A2:2012 (E) 15 For valves with modulating or step control, verify the declared opening and closing characteristics at rated voltage or current before and after the endurance test for conformity with 7.6.101 to 7.6.103. 7.7.3 Conversion of air flow rate Shall be according to #EN 13611:2007+A2:2011$, 7.7.3. 7.8 Durability Shall be according to #EN 13611:2007+A2:2011$, 7.8. 7.9 Performance test for electronic controls Shall be according to #EN 13611:2007+A2:2011$, 7.9. 7.10 Long-term performance for electronic controls Shall be according to #EN 13611:2007+A2:2011$, 7.10. 7.101 Closing function concerning remanence 7.101.1 Requirement Valves shall close automatically on reducing the voltage or current to 15 % of the minimum rated value. Valves with pneumatic or hydraulic actuating mechanisms shall close automatically on reducing the voltage or current to 15 % of the minimum rated voltage of the control valve. Valves shall close automatically on removal of the voltage or current of between 15 % of the minimum rated
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