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2007-12-24 11:50 |
8 Protection against access to live parts
8.1 Appliances shall be constructed and enclosed so that there is adequate protection against accidental contact with live parts.
Compliance is checked by inspection and by the tests of 8.1.1 to 8.1.3, as applicable, taking into account 8.1.4 and 8.1.5.
8.1.1 The requirement of 8.1 applies for all positions of the appliance when it is operated as in normal use, and after the removal of detachable parts.
NOTE This excludes the use of screw-type fuses and screw-type miniature circuit breakers which are accessible without the aid of a tool.
Lamps located behind a detachable cover are not removed, provided that the appliance can be isolated from the supply mains by means of a plug or an all-pole switch. However, during insertion or removal of lamps which are located behind a detachable cover, protection against contact with live parts of the lamp cap shall be ensured.
Test probe B of IEC 61032 is applied without appreciable force, the appliance being in every possible position except that appliances normally used on the floor and having a mass exceeding 40 kg are not tilted. Through openings, the test probe is applied to any depth that the probe will permit and is rotated or angled before, during and after insertion to any position. If the opening does not allow the entry of the probe, the force on the probe in the straight position is increased to 20 N. If the probe then enters the opening, the test is repeated with the probe in the angled position.
It shall not be possible to touch live parts or live parts protected only by lacquer, enamel, ordinary paper, cotton, oxide film, beads, or sealing compound except self-hardening resins, with the probe.
8.1.2 Test probe 13 of IEC 61032 is applied without appreciable force through openings in class 0 appliances, class II appliances and class II constructions, except for those giving access to lamp caps and live parts in socket-outlets.
NOTE Appliance outlets are not considered to be socket-outlets.
The test probe is also applied through openings in earthed metal enclosures having a nonconductive coating such as enamel or lacquer.
It shall not be possible to touch live parts with the test probe.
8.1.3 Instead of test probe B and test probe 13, for appliances other than those of class II, test probe 41 of IEC 61032 is applied without appreciable force to live parts of visibly glowing heating elements, all poles of which can be disconnected by a single switching action. It is also applied to parts supporting such elements, provided that it is obvious from the outside of the appliance, without removing covers and similar parts, that these supporting parts are in contact with the element.
It shall not be possible to touch these live parts.
NOTE For appliances provided with a supply cord and without a switching device in their supply circuit, the withdrawal of the plug from a socket-outlet is considered to be a single switching action.
8.1.4 An accessible part is not considered to be live if – the part is supplied at safety extra-low voltage, provided that
• for a.c., the peak value of the voltage does not exceed 42,4 V,
• for d.c., the voltage does not exceed 42,4 V,
or
– the part is separated from live parts by protective impedance.
If protective impedance is used, the current between the part and the supply source shall not exceed 2 mA for d.c., its peak value shall not exceed 0,7 mA for a.c. and
– for voltages having a peak value over 42,4 V up to and including 450 V, the capacitance shall not exceed 0,1F,
– for voltages having a peak value over 450 V up to and including 15 kV, the discharge shall not exceed 45 C.
Compliance is checked by measurement, the appliance being supplied at rated voltage.
Voltages and currents are measured between the relevant parts and each pole of the supply source. Discharges are measured immediately after the interruption of the supply.
NOTE Details of a suitable circuit for measuring the current are given in figure 4 of IEC 60990.
8.1.5 Live parts of built-in appliances, fixed appliances and appliances delivered in separate units, shall be protected at least by basic insulation before installation or assembly.
Compliance is checked by inspection and by the test of 8.1.1.
8.2 Class II appliances and class II constructions shall be constructed and enclosed so that there is adequate protection against accidental contact with basic insulation and metal parts separated from live parts by basic insulation only.
It shall only be possible to touch parts which are separated from live parts by double insulation or reinforced insulation.
Compliance is checked by inspection and by applying test probe B of IEC 61032, as described in 8.1.1.
NOTE 1 This requirement applies for all positions of the appliance when it is operated as in normal use and after removing detachable parts.
NOTE 2 Built-in appliances and fixed appliances are tested after installation. |
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