14.3DV D1
Modification: Delete the last three paragraphs beginning with “The leakage
current limit values...”.
15 Electric strength
15.1 The electric strength shall be adequate.
Compliance is checked by the tests of 15.2.
Protective impedance is disconnected from live parts before carrying out the tests.
The tests are made on the tools at room temperature and not connected to the supply.
15.2 The insulation is subjected for 1 min to a voltage of substantially sinusoidal waveform, having a
frequency of 50 Hz or 60 Hz. The value of the test voltage and the points of application are shown in Table
2, unless otherwise specified.
Accessible parts of insulated material are covered with metal foil.
Table 2 – Test voltages
Points of application of test voltage
Test Voltage (V)
Class III tools and
construction
Class II tools and
construction
Other tools
1. Between live parts and accessible parts separated from
live parts by
– basic insulation only
500
–
1 250
– reinforced insulation
–
3 750
3 750
2. For parts with double insulation, between metal parts
separated from live parts by basic insulation only, and
– live parts
–
1 250
1 250
– accessible parts
–
2 500
2 500
3. Between metal enclosures or covers lined with insulating
material and metal foil in contact with the inner surface of
the lining, if the distance between live parts and these metal
enclosures or covers, measured through the lining, is less
than the appropriate clearance as specified in 28.1
–
2 500
1 250
4. Between metal foil in contact with handles, knobs, grips
and the like and their shafts, if these shafts can become live
in the event of an insulation fault
–
2 500
2 500
5. Between accessible parts and internal diameter of cord
guard wrapped with metal foil
–
2 500
1 250
6. Between the point where a winding and a capacitor are
connected together, if a resonance voltage
U
occurs
between this point and any terminal for external conductors,
and
– accessible parts
1)
–
–
2
U
+ 1 000
– metal parts separated from live parts by basic insulation
only
–
2
U
+ 1 000
–
1)
The test between the point where a winding and a capacitor are connected together, and accessible parts or metal parts, is
only made where the insulation is subjected to the resonance voltage under normal running conditions. Other parts are
disconnected, and the capacitor is short-circuited.
Dostları ilə paylaş: 
