ABB VD4 Installation And Service Instructions Manual page 8

V D 4 - INSTALLATION AND SERVICE INSTRUCTIONS
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4. Description
• Auxiliary switch -BGB1 interrupts the circuit of the
optional additional shunt release OFF -MBO2 with
the circuit breaker in the open position, and the
circuits of shunt release ON -MBC and the optional
blocking magnet -RLE1 with the circuit breaker in
the closed position. There is one further NOC for
other purposes.
• On failure or absence of the control voltage,
blocking magnet -RLE1 mechanically locks the ON
half shaft and simultaneously acts on the
corresponding auxiliary switch -BGL1 to interrupt
the circuit of shunt release ON -MBC.
• Blocking magnet -RLE1 is accessible when front
plate 1.1 is removed.
• Auxiliary switch -BGB2 interrupts the circuit of
shunt release OFF -MBO2 with the circuit breaker
in the open position. One further NOC and three
NCCs are available for annunciation, control and
interlock purposes.
• Auxiliary switch -BGB3 can be optionally designed
with any possible combination of contacts from
five NOCs to five NCCs. Its contacts are available
for any required control, annunciation or interlock
functions. The auxiliary switch is normally
configured as shown in electrical diagrams.
• The single pole auxiliary switch -BGB4 (fleeting
contact time ≥ 30 ms) serves to provide a fault
signal ("breaker released").
With remote control, the auxiliary switch is
necessarily operated by:
• Shunt release OFF -MBO1 or
• Shunt release OFF -MBO2 or
• Undervoltage release -MBU or
• Indirect overcurrent release -MBO3.
Note:
1. Shunt releases OFF (-MBO1) and ON (-MBC) are
exclusively provided for opening and closing in
normal operation. For safety breaking operations,
the second shunt release OFF (-MBO2) must be
used, in most cases with a separate control
voltage supply.
These three releases are of the solenoid type and
suitable for a large number of operating cycles.
2. The undervoltage release (-MBU) and/or indirect
overcurrent release (-MBO3) are pure safety and
protection releases and must not be used for
switching in normal operation.
37 35 38
36 31 6
Figure 4/5: View of the stored-energy spring mechanism and auxiliary
equipment with the front plate removed
6 Recess for charging lever 9
31 Release and control mechanism on the drive shaft
34 Chain drive
35 Ratchet wheel
36 Charging motor
37 Release and control mechanism area
38 Auxiliary switch block
4.4.4 Mounting of the VD4 -63 kA on trucks from
other manufacturers
VD4 -63 kA generator circuit breakers which are not
installed on ABB withdrawable parts must be fitted
with one or two additional auxiliary switches which
are dependent on the mechanical lock and release
device. These must interrupt the circuit of shunt
release ON -MBC.
Similary to auxiliary switches -BGT2 and -BGT1 in
ABB withdrawable parts, no electrial pulse may
arrive during and before mechanical blocking of the
spindle mechanism, and may only be applied again
after the end of mechanical blocking.
This ensures that the shunt release ON cannot be
loaded with an electrical ON pulse when the
withdrawable part is in an intermediate position,
which could burn out the coil.
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