Peter electronic VersiComb II 230-3, Installation And Commissioning Instructions

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18 VC II 230/400-3...15
Fusing according to allocation type „2“:
The power semiconductors are to be protected by fuses of the utilization category gR
(semiconductor protection fuses, high-speed fuses). However, since these fuses do not ensure
line protection, it is necessary to use additionally line protection fuses (utilization category gL).
To protect the semiconductors it is necessary to select gR-fuses featuring cutoff-I²t-values which
are approx. 10-15% below the I²t-value of the power semiconductor (see technical data).
In this connection the fuse rating of the selected fuse should not be smaller that the starting
current to be expected for the soft start section and the braking current to be expected for the
braking section.
PETER electronic does not prescribe the use of semiconductor
protection fuses.
Note 1 On the basis of the I²t-value of the power semiconductors, the starting time,
possibly the max. starting current, braking time, braking current and
switching frequency, the fuse supplier is able to select a suitable type. Due to
the great variety of producers, sizes and types, PETER electronic does not
recommend any particular fuses.
Note 2 If the value of the fuse or the cutoff-I²t-value is selected too small, it may
happen that the semiconductor fuse reacts during the starting phase or
during braking.
Table 1
Column 1 Column 2 Column 3 Column 4 Column 5
Rated device
current
Start. section
Rated device
current
Brak. section
Device type Starting section
Fuse value
in the case of
allocation type 1
Braking section
Fuse value
in the case of
allocation type 1
12A 25A
SO9 = 45A
VCII 230-3
VCII 400-5.5 20A 20A
SO9 = 35A
15A 35A
SO9 = 60A
VCII 230-4
VCII 400-7.5 25A 25A
SO9 = 40A
25A 45A
SO9 = 75A
VCII 230-5,5
VCII 400-11 35/40A 35A
SO9 = 50A
32A 55A VCII 230-7,5
VCII 400-15 50A 40A