Powell 38PV40ARMM-4, Инструкционный бюллетень

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21 Equipment Description
01.4IB.65131
c. Blocking Interlock
Access to the emergency racking drive
is controlled by a blocking interlock.
The emergency racking access shutter
can only be opened with the circuit
breaker open. Moving the emergency
racking drive shaft shutter downward
prevents the closing of the circuit
breaker by operating a linkage which
blocks the mechanism. If the breaker
is not in the open position, the shutter
cannot be opened enough to insert
the racking handle. This interlock
ensures that the circuit breaker is
open when it is manually racked
into the compartment. Once the
circuit breaker reaches the operating
position and the shutter mechanism is
released, the circuit breaker can now
be closed. When the circuit breaker is
in the closed position, the shutter is no
longer free to move. This blocks the
operation of the emergency racking
drive shaft, deterring any attempt to
remove a closed circuit breaker from the
compartment.
2) Racking Mechanism
The racking mechanism consists of a
racking shaft (Figure 4, m) with racking
crank arms at each end, which are
supported by the frame side sheets. The
racking motor ( Figure 2, d ) is located at
the left end of the racking shaft, inside
the circuit breaker frame. In addition, the
racking crank arms have rollers attached to
each end of the racking shaft which engage
the vertical slots of the racking cams in the
circuit breaker compartment. Rotation
of the racking crank arms will drive the
circuit breaker into or out of the connected
position. This action also operates the
compartment shutters.
Automated racking operations are
monitored and controlled through current
sensing of the motor circuit. The motor
halts the racking operation when it
encounters the stop bolts.
Bolts on the left and right side sheets
provide a backup mechanical stop to the
crank arms. This positive stop prevents
further rotation of the racking shaft, thus
stopping circuit breaker travel.
D. c
IrcuIt
B
reAker
c
oMpArtMent
I
nterfAceS
1) Primary Disconnecting Devices
There are six primary disconnecting devices
( Figure 4, b & f ) on the circuit breaker. They
are arranged, two per phase, with the upper
device connected to the stationary end
of the vacuum interrupter, and the lower
device connected to the moving end of the
vacuum interrupter assembly.
!
CAUTION
Do not handle or move the circuit breaker by
the primary disconnecting devices as damage
may occur.
Each primary disconnecting device has
multiple contact fingers which will mate
with the stationary primary disconnecting
devices in the circuit breaker compartment.