Meeting IEC 60335 to ensure fire protection in unattended electrical household appliances


The IEC 60335 standard ensures better fire protection in unattended electrical household appliances. To achieve this goal, the demands placed on glow wire resistance of plastics used for insulating or mounting live components have been increased. The IEC 60335 standard on the ‘Safety of household and similar electrical appliances’ comprises two parts. Part 1 (IEC 60335-1) is the basic standard governing the majority of the general requirements placed on all electrical household appliances, while Part 2 is appliance specific and governs special features such as whether an appliance is deemed unattended or attended, the definition of the test procedures, tests concerning improper use as well as metrics including pollution degree. Part 1, Paragraph 30.2, ‘Test of heat and fire resistance’ defines various requirements for insulating plastics. As specified in the revised IEC 60335, insulating materials used for live components in unattended appliances whose current exceeds 0.2A must meet higher demands in glow wire testing. The plastic material’s after-flame times have been shortened accordingly. Part 2, Paragraph 30.2, defines whether an appliance is deemed to be attended or unattended and whether it uses the relevant components, such as fuse holders, appliance couplers, timers, circuit breakers for equipment, relays, motors and locks. Basically, the rule applies that appliances with a built-in timer or program controller or appliances operated by remote control are deemed unattended, while portable appliances are deemed attended.


In order to fulfil the glow wire requirements of unattended appliances, the plastic material of the components must pass the Glow Wire Flammability Index test (GWFI) & the Glow Wire Ignition Temperature test (GWIT). As an alternative to the GWIT, components may also undergo the Glow Wire Temperature test (GWT).


Connections >0.2 A


Material meets GWFI of > 850 ºC


Material meets GWIT of > 775 ºC Flame < 5s


Material approved


✓ YES


Part meets GWT of 750 ºC Flame < 2s


Surrounding Parts V-0 or V-1 Classification


Part approved ✓


schuRteR PRovIdes solutIons Manufacturers are challenged to test the compliance with these requirements. SCHURTER now provides the market with special versions of standard fuseholders and connectors that comply with these Glow Wire Tests. These items basically bear the number extension xxxx.xxxx.15. A detailed declaration of approval is included in the VDE certificate of the relevant product.


NO


Surrounding Parts Needle Flame Test


focus magazine - issue 10


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