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Iec 60335-1 Ed. 4.0
Safety of Household and Similar Electrical Appliances
This Standard deals with the safety of electrical
appliances for household and similar purposes;
the rated voltage of the appliances being not
more than 250 V for single-phase appliances and
480 V for other appliances.
Recently the Standard has been modified and requirements
are reportedly much stricter than those previously
used, in order to avoid fire risks and provide
further guarantees of safety in electrical appliances.
Such modifications involve, above all, components
made of an insulating material that support electrical
connections carrying a current >0.2A, including
components at a distance of less than 3 mm from
the connection.
The flowchart for the material and / or part evaluation
according to IEC 60335-1, is schematically
illustrated in figure.
Paragraph 30 - Resistance to heat and fire
- 30.1 - Heat resistance: the parts
must comply with the Ball Pressure Test of
IEC 60695-10-2. The test is carried out at
a temperature of 40°C ± 2°C
plus the maximum temperature rise determined
during the test of clause 11, but it shall
be at least 75°C ± 2°C for
external components and 125°C ±
2°C for components supporting live parts.
- 30.2 - Fire resistance
- 30.2.2 - Attended Appliances: according
to the Standard parts ought to be subjected
to the Glow-Wire Test of IEC 60695-2-11,
which is carried out at 750°C for
connections that carry a current >0.5A
and 650°C for other connections.
- 30.2.3 - Unattended Appliances
- 30.2.3.1: parts that carry a
current >0.2A shall have a Glow-Wire
Flammability Index of >= 850°C
(IEC 60695-2-12).
- 30.2.3.2: parts supporting current-carrying
connections, shall always be subjected
to the Glow-Wire Test according to IEC
60695-2-11. However, the GWT is not carried
out on parts of material classified as
having a Glow-Wire Ignition Temperature,
according to IEC 60695-2-13, of ³775°C
for connections that carry a current >0.2A
and >= 675°C for other connections.
Test samples ought to be no thicker than the
relevant part. The maximum flame-persistence-time
admitted during the test is of 5 seconds.
When the Glow-Wire Test of IEC 60695-2-11
is carried out on the parts, the temperatures
are of 750°C for connections which carry
a current >0.2A and 650°C for other connections.
If during the test a flame that persists for
longer than 2 seconds is produced, the Needle-Flame
Test must be carried out for all parts above
the connection within the envelope of a vertical
cylinder having a diameter of 20 mm and a height
of 50 mm. However, the latter test is not needed
if between the connections and the other parts
there is a “protection” that meets
the Needle-Flame Test.
The Needle-Flame Test is not carried out on
parts of material classified as V-0 or V-1,
according to IEC 60695-11-10, provided that
the test sample was no thicker than the relevant
part.
| Contact: |
email:
marketing@it.lati.com
LATI Industria Termoplastici S.p.A.
Via F. Baracca, 7 21040
Vedano Olona (VA) - Italia
Tel. : +390332409111 - Fax: +390332409307
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