TAVRIDA ELECTRIC ISM15_LD_1 Series, Application Manual

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Metal housin g
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Minimum Clearances due to Rated Ins ulation Voltage
The minimum clearances between the
blank phases and to earth shall be
according to VDE 0101.
The minimum clearances between phase to
phase and phase to earth are equal (Figure
24).
If the insulation cap set will not be used
the compliance with the rated insulation
level shall be approved by a voltage test.
Ur Up
Minimum
clearance (a)
15 kV 95 kV 120 mm
27 kV 125 kV 220 mm
Figure 24
Measures for Complying with the Rated Insulation Level
Insulation cap set for 27 kV ISM
To comply with the rated impulse
withstand voltage of 125 kV according
to ANSI 37.09 it is recommended to
cover the top connections of the 27kV
ISM with an insulation cap set.
The insulation cap set is included in the
scope of supply of the affected ISM.
The arrangement is shown in Figure 25.
Figure 25
Busbar for 27 kV ISM
If the PCD of the 27kV ISM is 210 mm, the
connected bus bars shall have the shape
as shown in Figure 26.
40
R5
10
Figure 26
Phase segregation plates
for 15 kV and 27 kV ISM
For 15 kV ISM with a PCD of 150 mm or
27 kV ISM with a PCD of 210 mm it is
recommended to use segregation plates
between the poles. Minimum size and
position of the plates are shown in
Figure 27.
If the plates will not be used the compli-
ance with the rated insulation level shall
be approved by a voltage test.
The segregation plates are not included in
the scope of supply.
Recommended size and position of
the segregation plates for ISM, 15 kV
PCD 150 mm
Recommended size and position of
the segregation plates for ISM, 27 kV
PCD 210 mm
265
370
150
265
400
150
Figure 27
Section AA
45
°
A
A
A
A
Upper cover par t
Sealing ring
Support insulator
Cap for upper
connecting bolt
Lower cover par t
A
A
A
A
Upper cover par t
Sealing ring
Support insulator
Cap for upper
connecting bolt
Lower cover par t
3