GE Industrial Solutions PowerVac PV-VL 13.8-1000-0 and -1 - Manual (Page 29)

GEH 6468A - Power/Vac VL Breaker Page 29
8.2. CLOSING OPERATION. (REFER TO FIG.
23)
By either energizing the close solenoid or
depressing the manual close button, the close latch
(8, view C) is rotated, releasing the closing spring
(1, view B). This action releases the energy in the
closing spring and transmits it to the closing cam
(9, view D) and closing roller (10, view D) causing
the linkage to rise until the close prop (11, view D)
can slip under the close roller (10, view D) and
hold the linkage in place. As the linkage moves,
the output crank (12, view D) rotates the cross
shaft (13, view D) which in turn rotates the phase
bell cranks (14, view E) on all three poles. The
rotation of the phase bell cranks compresses the
two opening springs (15, view E) on poles 1 and 3,
closes the vacuum interrupters, and compresses
the wipe springs (16, view E) on each pole. The
rotation of the cross shaft (13, view D) also
changes the auxiliary switch (7, view D) position.
The position flag on the front panel will then
indicate "CLOSED". After the breaker is closed, the
charging motor is again energized and the closing
spring is charged as described under "CLOSE
SPRING CHARGING". Spring charging is possible
when the breaker is in the closed position because
the linkage is held in place by the prop.
8.3. OPENING OPERATION. (REFER TO FIG.
23)
By either energizing the trip solenoid (18, view B)
or depressing the manual trip button (23, view B),
the trip latch (19, view D) is rotated, permitting the
linkage to collapse. The vacuum interrupter
contacts will then open under the force of the wipe
springs (16, view E) and opening springs (15, view
E). At the end of the opening stroke, the center
phase wipe spring assembly hits a stop on the
frame limiting overtravel and rebound. Rotation of
the cross shaft from the closed to the open position
operates the auxiliary switch (17, view D) opening
the trip coil circuit. When the closing spring has
been recharged, the linkage is reset allowing the
trip latch to rest in place on the trip roller, ready for
another closing operation.
If the closing spring has not been recharged, the
trip latch will be held out of position. A latch-
checking switch (LCS) (21, view C) will not close
unless the latch is in its normal position. The
contacts of the latch-checking switch are part of
the closing circuit and will not allow for an electrical
close until the latch is reset.
8.4. TRIP FREE OPERATION.
The linkage is mechanically trip-free in any
location
on the closing stroke. Electrically energizing the
trip coil while closing will, after the auxiliary switch
contacts change position, rotate the trip latch and
permit the circuit breaker to open fully. The linkage
will reset as in a normal open operation and the
closing spring will recharge as described under
"CLOSE SPRING CHARGING".
9. CONTROL CIRCUIT
A typical PowerVac
®
VL circuit breaker ML-18VL
mechanism wiring diagram is shown in Fig. 8 and
9. Check the wiring diagram supplied with the
actual circuit breaker for its wiring.
The close spring charging motor circuit is
established through the Close Latch Monitor Switch
(CL/MS) if the close latch is reset and the Spring
Motor Limit Switch (SM/LS) if the closing spring is
discharged. When the closing spring is charged,
the SM/LS interrupts the circuit.
The close coil circuit is established through two
normally closed 52Y relay contacts, and the Latch
Checking Switch (LCS), if the trip latch is reset. An
auxiliary switch contact 52B is also in series with
the close coil and closes when the breaker is open
and opens when the breaker is closed. During a
close operation, cam rotation closes the SM/LS
contact allowing the 52Y relay to be energized. The
52Y relay opens its contacts, in the close coil
circuit and seals itself in through one of its own
contacts. This seal-in action prevents reclosing on
a sustained close command. The close signal must
be removed to drop out the 52Y relay and
reestablish the closing circuit. This provids an anti-
pump feature.
Circuit breaker-mounted auxiliary switch contacts
not used in the control circuit are brought out for
control and indication functions. The metal-clad
equipment may provide a breaker-operated
stationary auxiliary switch for additional contacts.
10. MECHANICAL CHECKING AND SLOW
CLOSING
10.1. VISUAL INSPECTION
Visually inspect the circuit breaker for any signs of
damage or loose hardware.
10.2. CLOSING SPRING CHARGING
Manually charge the breaker closing spring using
the charging handle provided (1, Fig. 18). The
closing spring is charged by a ratcheting
mech-