Safety Related Electronic Control Systems
in Gas Appliances
燃气用具电控系统的安全性
Copyright © 2012 BSI. All rights reserved.
BSI 英国标准协会
• A global independent business services organization
全球性的第三方服务机构
• BSI Group established in 1901 and was incorporated by Royal
Charter in 1929
BSI集团建立于1901年，1929年获得皇家特许
• The world’s first national standards body and is the national
standards body for the UK
BSI是英国国家标准机构，世界上第一家国家标准机构
• The Group is made up of business in Standards, Assessment &
Management Systems, Training, Product Testing and
Governance, Risk & Compliance (GRC)
BSI的业务范围包括，标准和标准化；评估和管理体系；培训；产品
测试以及管理、风险和符合性（GRC）
• 2,500 employees in 110 countries
在110个国家有2,500名员工
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Meet the Trainer 讲师简介
Graham McKay
Global Head of Electrical & Gas Products 全球电气和燃气器具认证主管
• Electronic engineering graduate 电子工程专业
• 10 years Designing safety-critical electronic controls for British Gas 英国燃气10年安全性电控设计
• Previously head of BSI product testing and “Notified Body” operations 曾任BSI产品测试和“公告指
定认证机构”运营主管
• Long-time member of many CEN committees for gas appliances (esp EN298) 多个欧盟燃气用具
标委会资深成员，特别是EN 298
• Founder member of “GAD-AC” that advises European Commission on gas safety 欧盟燃气安全咨
询委员会”GAD-AC”的创始成员
• Provided training to CSA, AGA, JIA, KGS, Bosch, Noritz, Rinnai, Vanward… and others 给多家认证
机构和燃气用具制造商提供培训
http://uk.linkedin.com/in/grahammckay/
Graham.mckay@bsigroup.com
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Background 背景
• Gas appliances are required to be SAFE 燃气用具必须是安全的
Can control and safety devices affect this? 控制与安全装置会影响安全性吗？
• Standards include requirements for all control devices? 标准是否包括了所有控
制装置的要求？
• What about…
• An electronic spillage detector on an open-flued gas fire? 烟道式燃气壁炉的
燃气逃逸探测器？
• A remote control for a gas cooker? 燃气炊具的遥控？
• An electronic overheat thermostat on a tumble dryer? 滚筒式烘干机的过热
温控器
• Wi-Fi, Bluetooth, iPhone Apps…? 无线网络连接、蓝牙、iPhone应用软件…?
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FACT 现实
• Technology in development of electronic controls is moving MUCH faster than the
standards-making process. So standards will often be hard to relate to the
products that are submitted for evaluation. 电子控制器的技术发展比标准制定要
快得多，因而，经常发生标准很难用于一些产品的评价。
• So, we need to TAKE CARE when checking controls and control systems used in
appliances to ensure that they are safe. 由此，我们要谨慎，以确保燃气用具控制
器和控制系统的安全性
• This is especially true for novel electronic control systems where we need to
ensure that they meet equivalent levels of safety to established devices. 对于新
型电控系统，要确保其满足已有装置相当的安全性水平，这显得尤为重要。
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New risks…新的风险
• Technology can bring many advantages to the type of equipment
that we use, such as: 新技术可以给设备带来许多优点，例如：
• Increased efficiency (using feedback for more precise control) 能效的提高
（利用反馈信息，达成更精确控制）
• Better user interfaces, making appliances easier to operate 更好的用户界
面，让使用更简便
• Diagnostics to aid fault finding… 故障诊断… …
• But technology can introduce new risks as well… 然而，新技术也可能引入新
的风险… …
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New technology = New risks…新技术 = 新风险
• Conventional gas fire with
mechanical controls… 传统
的燃气壁炉用机械控制器
• Safety is well understood and covered by standards established
over many years 其安全性广为了解，多年来已经包括在众多的
标准中
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New technology = New risks…新技术 = 新风险
• Addition of remote control system… 遥控系统的加入
• What new risks have been added? 什么新的风险随之引入？
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New technology = New risks…新技术 = 新风险
• Product can now be operated by small children?
壁炉现在可以由幼童操作？
• Product may be switched on accidentally? 壁炉可
以被意外点燃？
• Control system faults may cause fire to come on
unexpectedly? 控制系统失灵导致壁炉不随人意？
• Interference (EMC) may cause fire to come on
unexpectedly? 电磁干扰可以导致壁炉不随人意？
• Other devices may also operate our gas fire? 其它
装置也可以操作该壁炉？
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New technology = New risks新技术 = 新风险
• Real world example of what can go wrong… 现实生活中可
能出错的例子
• We have to try and minimise these risks 我们必须尽力减少这
些风险
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New risks?新风险？
• What about a central heating boiler with a remote control? What new
risks would be introduced now? 遥控集中供热锅炉呢？有何新风险？
• Risks arise from the APPLICATION – not the technology 风险来自使用
而不是技术
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Dealing with Electronic Controls 电控安排
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Safety with electronic controls 电控的安全性
•
Situation is often complex (and standards less helpful) so we need to develop a
strategy for dealing with these. 情形通常是复杂的（加之标准的缺乏完全表达），
因而，我们得有对策
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•
What standard applies to this water heater
control? 哪个标准适用于该热水器控制器？
•
Depends what it is intended to do! 基于其用
途！
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Control classifications 控制器分类
To establish the standard that applies to the electronic control and
the detailed tests that need to be applied, electronic controls need
to be classified into one of three types: 考虑标准的建立、具体测试
的实施，控制器要分为三类

Class A A类

Class B B类

Class C C类
NB: Classification applies to gas and electrical appliances
注：分类适用于燃气和电气用具
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Class A A类
“Control functions which are not intended to be relied upon for the
safety of the equipment.” 控制功能不关乎设备的安全性
Examples of controls which include Class A functions are: A类控制器的例子





Room thermostats 房间温控器
Humidity controls 湿度控制器
Lighting controls 照明控制
Pump speed controls 泵速控制
Time switches for appliances that can safely operate whilst unattended 定
时开关用于无人在场时设备的安全运行
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Class A A类
By definition, Class A controls can have no affect on the functional safety of
an appliance, so: 根据定义，A类控制器不能影响设备的功能安全性
• They are not covered by the scope of the GAD 不在燃气用具指令范围
• Hazards are purely electrical in nature (Electric shock or fire) 纯粹的电气危害
（电气短路或火灾）
• Only testing to standard such as EN60730-1 is required to cover hazards 测试
标准是EN 60730-1
A good test is… “If I replaced this control with a mechanical switch, would
the appliance remain safe?” 可以一试，如果换上一个机械开关，设备依旧安
全？
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Class B B类
“Control functions intended to prevent unsafe operation of the
controlled equipment.” 控制器功能是防止受控设备的不安全运行
These controls have no direct affect on the safety of an appliance but are
used to protect against unsafe conditions caused by other failures that may
occur. 这些控制器不直接影响设备的安全性，但是用于防御一些缺失导致的不
安全条件
Examples of controls which include Class B functions are: B类控制器的例子
• Electronic overheat controls 电子过热控制器
• Air-flow sensing controls 空气流量传感控制器
• Door locks for laundry equipment 洗衣设备的门锁
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Class B B类
These controls generally fall within the scope of the GAD as they are
designed to guard against specific hazards 这些控制器一般在燃气用具指令
范围内，因为通常是针对特定危害而设计的
Safeguard 防护
Hazard 危害
Air flow sensor 空气流量传感器
Poor Combustion 不充分燃烧
Electronic Thermal cut-out 电子热阻断器 Overheating 过热
In addition to electrical safety testing these controls will need to undergo
further analysis for functional hazards 除了电气安全测试以外，对这些控制
器还要进行进一步功能性危害分析
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Class C C类
“Control functions which are intended to prevent
special hazards (e.g., explosion of the controlled
equipment)” “控制器的功能是防止特定的危害（例如，
所控制设备爆炸）
Controls whose failure can directly cause a hazardous
condition to occur. 控制器的缺失会直接导致危害条件成立
Examples of controls which may include Class C functions: C
类控制器的例子
• Automatic burner controls – EN 298 自动点火控制 – EN 298
• Electronic air/gas ratio controls (GARC’s) – EN 12067-2 电子
空气燃气比控制器（GARC’s）– EN 12067-2
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Class C C类
Class C controls typically have direct control of at least one safety
critical device (e.g. gas valve or heating element). C类控制器具有对
至少一个安全性关键装置（例如，燃气阀门或加热单元）的直接控制
Safety requirements are given in standards such as: 很多标准包括了
安全性要求，例如：
• EN 298 (Gas burner control systems) EN 298（自动点火控制系统）
• EN 12067-2 (Air/Gas ratio controls) EN 12067-2（电子空气燃气比控制
器）
• EN 60730-1 (Controls for household electrical appliances) EN 60730-1
（家用电器的控制器）
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Examples… 例子
Type of Control System 控制系统
Class? 类别
Electronic room thermostat for heating boiler
供热锅炉系统的电子房间温控器
Single electronic thermostat on gas water heater
燃气热水器电子温控器
Electronic control thermostat PLUS separate electronic
overheat thermostat on gas water heater
燃气热水器电子温控器外加过热温控器
Single electronic thermostat on gas oven
燃气烤炉电子温控器
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Examples…例子
Type of Control System 控制系统
Electronic room thermostat for heating boiler
Class?类别
A
供热锅炉系统的电子房间温控器
Single electronic thermostat on gas water heater
Electronic control thermostat PLUS separate electronic
overheat thermostat on gas water heater
Single electronic thermostat on gas oven
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Examples…例子
Type of Control System 控制系统
Class?类别
Electronic room thermostat for heating boiler
A
Single electronic thermostat on gas water heater
C
燃气热水器电子温控器
Electronic control thermostat PLUS separate electronic
overheat thermostat on gas water heater
Single electronic thermostat on gas oven
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Examples…例子
Type of Control System 控制系统
Class?类别
Electronic room thermostat for heating boiler
A
Single electronic thermostat on gas water heater
C
Electronic control thermostat PLUS separate electronic
overheat thermostat on gas water heater
A+B
燃气热水器电子温控器外加过热温控器
Single electronic thermostat on gas oven
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Examples…例子
Type of Control System 控制系统
Class?类别
Electronic room thermostat for heating boiler
A
Single electronic thermostat on gas water heater
C
Electronic control thermostat PLUS separate electronic
overheat thermostat on gas water heater
Single electronic thermostat on gas oven
A+B
A*
燃气烤炉电子温控器
* Most likely answer – would have to test to be sure. 最可能的答案 – 必须测试才能确定
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Examples…例子
Type of Control System 控制系统
Electronic room thermostat for heating boiler
供热锅炉系统的电子房间温控器
Single electronic thermostat on gas water heater
燃气热水器电子温控器
Electronic control thermostat PLUS separate electronic
overheat thermostat on gas water heater
燃气热水器电子温控器外加过热温控器
Single electronic thermostat on gas oven
Class?类别
A
C
A+B
A*
燃气烤炉电子温控器
* Most likely answer – would have to test to be sure. 最可能的答案 – 必须测试才能确定
Remember that the APPLICATION determines the class of the control
切记，是应用决定控制器的分类
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Real world controls 现实中的控制器
• It is common for a control to contain a mix of two or more of the classes of electronic
system: 众所周知，一个控制器包含两个或多个电子系统类别
Air proving (Class B)
Control thermostat
(Class A)
Burner control
(Class C)
Air proving 空气探测 B类；Control thermostat 温控器 A类；Burner control 点火控制器 C类
• In this case it is necessary to assign the appropriate class to each FUNCTION of the
system so that we can do the correct testing. 如此， 必须对每个功能确定合适的类别，这
样才能进行正确的测试
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Process 流程
Risk assessment for application of electronic control
电控应用的风险评估
Determine required safety class
(A, B or C) from assessment
根据评估，确定安全分类（A, B或C）
Apply relevant EN or IEC standard
采用相关的EN或IEC标准
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Testing regime for classes 分类测试规则
In general, European and IEC safety standard require the following
levels of “fail-safety” of electronic controls: 通常，欧盟标准（EN）
和国际标准（IEC）要求控制器达到下述“故障-安全”水准



Class A – Single fault (electrical hazards only) 单一故障（仅电气危
害）
Class B – Single fault (functional & electrical hazards) 单一故障（性
能和电气危害）
Class C – Two independent faults (functional & electrical hazards)
两个独立的故障（性能和电气危害）
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Applicable European Standards 现行的欧盟标准

EN 298: 2012
制系统
Electronic Burner Control Systems for gas & oil 点火控
(NB: 2003 edition withdrawn in 2015 2003版在2015年废除)

EN 12067-2: 2004 Electronic Gas/Air Ratio Controls 燃气空气比例控制

EN 14459: 2007 Electronic Control Systems for Gas Appliances 燃气用
具的电子控制系统

EN 60730-1: 2011 Electrical Controls for Household & Similar Use 家用电
器控制器

EN 60730-2-9: 2010 Temperature sensing controls 温度传感控制器

EN 13611: 2007 Safety & Control Devices for Gas Appliances 燃气用具
的安全和控制装置
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Applied to our real-world control 应用于实际控制器
EN 12067-2
Gas/Air ratio control
Burner control
Control thermostat
EN 60730-2-9
EN 298
Standards need to be applied carefully!标
准的使用要谨慎
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Summary 概要






Technology is moving fast… 技术发展迅速
Standards cannot keep up with the pace of new inventions 标准不能保持与
新技术同步
Regulators and approval bodies need to adapt 管理者和认证机构要适应，
通权达变
Standards no longer give us all the answers 标准不再提供所有答案
Risk assessment and “thinking on your feet” has become the norm 风险评
估和“独立思考”已然成为准则
Choose the best partners to help you through the assessment 选择最好的
合作伙伴，帮助您评估
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