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ANNEXES
נספחים
Table G.1 - correspondence between the nominal voltage of the supply system and the equipment rated impulse withstand voltage
Preferred values of rated impulse withstand voltage (1.2/50ԋs)
at 2000 m kV
Nominal voltage of the supply ( ≤ rated insulation voltage of the equipment )
Overvoltage category
I
II
III
IV
Specially
protected
level
Load (appliance,
eguipment) level
Distribution
circuit level
Origin of
installation
(service
entrance level)
0.33
0.5
0.8
1.5
12.5 , 24, 25, 30, 42, 48
0.5
0.8
1.5
2.5
60
66
66/115
0.8
1.5
2.5
4
220-110, 240-120
110, 120
115,120,127
120/208,127/220
1.5
2.5
4
6
440-220
220
220,230,240,260,277
220/380,230/400,
240/415,260/440, 277/480
2.5
4
6
8
960-480
480
347, 380, 400, 415, 440, 480,
500, 577, 600
347/600,380/660,
400/690,415/720, 480/830
4
6
8
12
1000
660, 690, 720, 830, 1000