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Components and IEC 60335-1
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IEC 60335-1 household appliances
Enhanced requirements on components
The IEC 60335-1 standard in its 4th edition ensures even better fire protection in unattended electrical household appliances. To achieve this goal, the demands placed on glow
wire resistance of the plastics used for insulating or mounting live components have been
increased. Household appliances may catch fire due to power surges (glowing components), defective components, faulty electrical connections, arcing switching contacts,
etcetera.
Part 1, paragraph 30.2, "Test of heat and fire
resistance" (see Figure 1), defines various requirements for insulating plastics. As specified in
the revised 4th edition of IEC 60335-1 (which
came into effect in May 2001), insulating materials used for live components in unattended
appliances whose current exceeds 0.2 A must
meet higher demands in glow wire testing. The
plastic materials' after-flame times have been
shortened accordingly.

Requirements for components used in
unattended appliances rated at >0.2 A

The insulation materials used in close proximity
(<3 mm distance) to the electrical conductor in
appliances of this category must undergo two
tests (see Figure 2). These are the GWFI (Glow
Wire Flammability Index) and the GWIT (Glow
Wire Ignition Temperature).

Parts of Non-Metallic Materials
in Household Equipment,
IEC 60335-1, Chapter 30.2
Test of Heat and Fire Resistance

Attended Appliances
Chapter 30.2.2

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
(IEC 60335-2-xx), see Table 1, is appliancespecific and governs special features such as
whether an appliance is deemed unattended or
attended, the definition of the test procedures,
tests concerning the improper use as well as
distance measures including pollution degree.
IEC 60335-2-5

Ranges and ovens

IEC 60335-2-7

Washing machines

IEC 60335-2-9

Portable cooking appliances

IEC 60335-2-12

Cup warmers

IEC 60335-2-14

Misc. kitchen appliances

IEC 60335-2-24

Cooling appliances

IEC 60335-2-30

Heaters

IEC 60335-2-36

Professional cooking appli ances

IEC 60335-2-40

Heat pumps, air conditioners

IEC 60335-2-51

Circulation pump

IEC 60335-2-60

Whirlpools

IEC 60335-2-84

Toilets

Connections
> 0.2 A

Unattended Appliances
Chapter 30.2.3

Connections
> 0.5 A

Connections
< 0.2 A

Connections
> 0.2 A

Part must
Part must
meet GWT of meet GWT of
650 °C
750 °C

Material must
meet GWIT of
>675 °C
or
Part must
meet GWT of
650 °C

See figure 2
Regulations
have been
stringent

Figure 1: Overview of plastic components
in electrical household appliances

Dishwashers

IEC 60335-2-6

Connections
< 0.5 A

See figure 1

Table 1: Examples according to household
appliances standard, Part 2

Part 2, paragraph 30.2, defines whether an appliance as defined is to be deemed 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 to be deemed unattended, while portable appliances are to be deemed attended. However, there may also be
attended and unattended versions within a Part
2 standard, e.g. the grill with or without timer
as specified in IEC 60335-2-6. The transition
period, during which appliance manufacturers
were still allowed to use components not covered by the standard, has expired in the meantime for all appliances approved in accordance
with IEC 60335-1.

Products

Material meets
GWFI of >850 ºC

Part meets
GWT of 750 ºC
Flame <2s

Material meets
GWIT of >775 ºC
Flame <5s

No
Material
approved

Yes
Surrounding
Parts V-0 or V-1
Classification

Surrounding
Parts Needle
Flame Test

Part
approved

Figure 2: Overview of approval of components used in unattended appliances

The aim of these tests:
•t The GWFI, using a glow wire, establishes
the materials' self-extinguishment/afterflame
behavior in the event of an open fire. This
test corresponds to the after-flame test according to UL 94. During the GWFI test (see
Figure 3) the material, while allowed to ignite
at 850 °C, must self-extinguish within less
than 30 seconds after the removal of the
glow wire. The materials are tested in the
form of plates of varying thickness according to IEC 60695-2-12. The material tested
must meet this requirement otherwise no
approval is possible.

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