IEC_60335-2-21.pdf

-2-60335-2-21IEC:2002(E)CONTENTSFOREWORD.3INTRODUCTION61 Scope.72 Normative references.73 Definitions.74 General requirement.95 General conditions for the tests96 Classification.97 Marking and instructions.98 Protection against access to live parts.109 Starting of motor-operated appliances.1010 Power input and current.1011 Heating.1012 Void.1113 Leakage current and electric strength at operating temperature.1114 Transient overvoltages.1115 Moisture resistance.1116 Leakage current and electric strength.1117 Overload protection of transformers and associated circuits.1118 Endurance.1119 Abnormal operation.1120 Stability and mechanical hazards.1221 Mechanical strength.1222 Construction.1223 Internal wiring.1524 Components.1525 Supply connection and external flexible cords.1626 Terminals for external conductors.1627 Provision for earthing.1628 Screws and connections.1629 Clearances,creepage distances and solid insulation.1630 Resistance to heat and fire.1631 Resistance to rusting.32 Radiation,toxicity and similar hazardsAnnexes.20Bibliography.21Figure 101-Examples of types of storage water heaters.18Figure 102-Examples of positions of the thermocouples.980335-2-21IEC:2002(E)-3-INTERNATIONAL ELECTROTECHNICAL COMMISSIONHOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES-SAFETY-Part 2-21:Particular requirements for storage water heatersFOREWORD1)The IEC(International Electrotechnical Commission)is a worldwide organization for standardization comprisingall national electrotechnical committees(IEC National Committees).The object of the IEC is to promoteinternational co-operation on all questions concerning standardization in the electrical and electronic fields.Tothis end and in addition to other activities,the IEC publishes International Standards.Their preparation isentrusted to technical committees;any IEC National Committee interested in the subject dealt with mayparticipate in this preparatory work.International,governmental and non-governmental organizations liaisingwith the IEC also participate in this preparation.The IEC collaborates closely with the InternationalOrganization for Standardization(ISO)in accordance with conditions determined by agreement between thetwo organizations.2)The formal decisions or agreements of the IEC on technical matters express,as nearly as possible,aninternational consensus of opinion on the relevant subjects since each technical committee has representationfrom all interested National Committees.3)The documents produced have the form of recommendations for international use and are published in the formof standards,technical specifications,technical reports or guides and they are accepted by the NationalCommittees in that sense.4)In order to promote international unification,IEC National Committees undertake to apply IEC InternationalStandards transparently to the maximum extent possible in their national and regional standards.Anydivergence between the IEC Standard and the corresponding national or regional standard shall be clearlyindicated in the latter.5)The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for anyequipment declared to be in conformity with one of its standards.6)Attention is drawn to the possibility that some of the elements of this International Standard may be the subjectof patent rights.The IEC shall not be held responsible for identifying any or all such patent rights.This part of International Standard IEC 60335 has been prepared by IEC technical committee61:Safety of household and similar electrical appliances.This fifth edition cancels and replaces the fourth edition published in 1997 and itsamendment 1(1999).It constitutes a technical revision.The text of this part of IEC 60335 is based on the following documents:FDISReport on voting61/2135/FDIS61/2160/RVDFull information on the voting for the approval of this standard can be found in the report onvoting indicated in the above table.This part 2 is to be used in conjunction with the latest edition of IEC 60335-1 and itsamendments.It was established on the basis of the fourth edition(2001)of that standard.NOTE 1 When Part 1 is mentioned in this standard,it refers to IEC 60335-1.This part 2 supplements or modifies the corresponding clauses in IEC 60335-1,so as toconvert that publication into the IEC standard:Safety requirements for electric storage waterheaters.-460335-2-21 IEC:2002(E)When a particular subclause of Part 1 is not mentioned in this part 2,that subclause appliesas far as is reasonable.When this standard states addition,modification,or replacement,the relevant text in Part 1 is to be adapted accordingly.NOTE 2 The following numbering system is used:-subclauses,tables and figures that are numbered starting from 101 are additional to those in Part 1;-unless notes are in a new subclause or involve notes in Part 1,they are numbered starting from 101,includingthose in a replaced clause or subclause:-additional annexes are lettered AA,BB,etc.NOTE 3 The following print types are used:-requirements:in roman type;-test specifications:in italic type;-notes:in small roman type.Words in bold in the text are defined in Clause 3.When a definition concerns an adjective,the adjective and theassociated noun are also in bold.The committee has decided that the contents of this publication will remain unchanged until2004.At this date,the publication will bereconfirmed;withdrawn;replaced by a revised edition,or amended.The following differences exist in the countries indicated below.-6.1:Class OI appliances are allowed(Japan).-6.2:IPX0 water heaters are allowed(France,Portugal,United Kingdom and USA).-7.1:Additional markings are required(Australia,New Zealand and South Africa).-7.1:The rated pressure is to be marked in pounds per square inch(USA).-7.1:Open outlet water heaters are not required to be marked with rated pressure(USA).-7.12.1:Additional instructions are required(South Africa).-11.7:The test is different(USA).-19.1:Water heaters that have all four features and are not liable to be emptied in normal use are not subjectedto the test of 19.101(South Africa).-19.1:Appliances incorporating sheathed heating elements are not required to have an outer enclosure of metalbut their rated power input is limited to 12 kW(USA).-19.101:The test is different(USA).-22.101:Pressure reducing valves have to be designed for an inlet pressure of 2 MPa(South Africa).-22.101:The minimum rated pressure is 1,0 MPa(Denmark,Finland,Norway and Sweden).-22.102:The minimum pressure is 2,1 MPa.The test is not carried out on water heaters having a capacity lessthan 2 I or on appliances having containers open to the atmosphere(USA).-22.103:Closed water heaters have to incorporate a pressure-relief device(Norway).-22.103:Closed water heaters have to incorporate a pressure-relief device sensitive to both pressure andtemperature that operates before the water temperature reaches 99 C(Australia and New Zealand).-22.103:Closed water heaters having a capacity exceeding 50 I or a rated power input exceeding 2 kW have toincorporate a pressure-relief device sensitive to both pressure and temperature that operates before the watertemperature reaches 99 C(South Africa).-22.103:Closed water heaters have to incorporate a temperature relief valve or a combined temperature andpressure-relief valve that operates before the water temperature reaches 100*C(United Kingdom).-22.106:All water heaters have to incorporate a thermal cut-out(India).-22.106:The thermal cut-out of single-phase closed water heaters need only provide single-pole disconnection(Japan).60335-2-211EC:2002(E)-5-22.106:For all closed water heaters,the thermal cut-out is to provide all-pole disconnection(France,Netherlands,Norway and Switzerland).-22.109:A tool is not required for draining the appliance(Canada and USA).-22.110:Additional requirements apply to plastic or resin-based containers(South Africa).22.112:The temperature limit is 95 C(South Africa).22.112:The temperature limit is 85 C(USA).24.101:Thermal cut-outs are required to have a trip-free switching mechanism(USA).-24.102:The maximum water temperature is 90C(Australia and New Zealand).-24.102:The maximum water temperature is 99C(Japan,Norway.Portugal,United Kingdom and USA)-24.102:The temperature limit of 130C is only allowed for closed water heaters having a rated pressure of atleast 0,4 MPa(South Africa).