Siemens SION 3AE6113-0, Руководство по эксплуатации

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Description
9229 0020 176 0B 29
2019-04-02
Ambient conditions
Installation altitudes
Insulating capacity The insulation capacity of insulation in air declines with rising altitude increases due
to the lower air density. As per IEC 62271-1, the rated lightning impulse withstand
voltage values given in Fig. 32 are valid up to an installation altitude of 1000 m
above sea level.
Above an altitude of 1000 m, the insulation level must be corrected as shown in
Fig. 34:
Occasional condensation may occur under these ambi-
ent conditions.
Vacuum circuit-breakers SION
®
are suitable for use in
the following climate classes according to IEC 60721,
part 3-3:
Class
• Climatic ambient conditions:
3K4
1)
• Biological ambient conditions: 3B1
• Mechanical ambient conditions: 3M2
• Chemically active substances:
3C2
2)
• Mechanically active substances:
3S2
3)
1) Minimum temperature limit: -5 °C (with addition A40 to -25 °C)
2) Without occurrence of salt fog and simultaneous condensation
3) Restriction: Clean insulation parts
4) Average value, measured over 24 hours
5) Average value, measured over 1 month
Fig. 33 Ambient conditions
+40 °C
-5 °C
1)
95 %
4)
90 %
5)
5 %
U ≥ U
0

K
a
U Rated withstand voltage U under standard reference
atmosphere
U
0
Required rated withstand voltage for the installation
location
K
a
Altitude correction factor
K
a
= e
m

(H - 1000)/8150
Calculating the altitude correction factor K
a
:
H = Site altitude in metres
m = 1 for AC voltage, lightning impulse withstand volt-
age (between phases, phase-ground, applied lon-
gitudinally)
Example
For a required rated withstand voltage of 75 kV at an al-
titude of 2500 m, an insulation level of at least 90 kV un-
der standard reference atmosphere conditions is
required:
90 kV ≥ 75 kV

e
1

(2500 - 1000)/8150
≈

75 kV

1.2
Fig. 34 Altitude correction factor K
a