GE Industrial Solutions PowerVac PV-VL 13.8-1000-0 and -1 - Manual (Page 30)

Page 30 GEH 6468A - Power/Vac VL Breaker
anism that advances one ratchet tooth at a time.
When the spring is fully charged, the spring load is
held by the closing latch. The spring indicator (6,
Fig. 16) changes from "DISCHGD" to "CHARGED',
and a positive snap is be heard as the spring
travels over center.
CAUTION: AFTER THE SPRING IS COM-
PLETELY CHARGED, AS INDICATED ABOVE,
FURTHER FORCING THE CHARGING HANDLE
MAY CAUSE DAMAGE TO THE CLOSING
LATCH AND ITS ASSOCIATED PARTS.
10.3. CLOSING SPRING GAG
Removing the mechanism cover and inserting the
tip of the closing spring gag tool (3, Fig. 19)
between the end of the spring and the spring guide,
engaging the détentes on the gag tool into the slots
in the closing spring guide.
With the gag tool in position depress the manual
close button. This action will partially discharge the
closing spring and also partially close the vacuum
interrupter contacts. Do not energize the secondary
control circuit at this time.
CAUTION: USE OF THE GAG TOOL SHOULD
ONLY BE ATTEMPTED WHEN THE BREAKER IS
OUT OF THE CUBICLE.
10.4. SLOW CLOSING
To manually slow close the breaker contacts,
install the closing spring gag, as described above.
Put the manual charge handle on the manual
charge lever and move the handle up and down.
The breaker will be fully closed when the spring
charge indicator shows "CHARGED"
CAUTION: WITH THE GAG TOOL INSTALLED,
THE BREAKER CLOSED, AND OPENING
SPRINGS CHARGED, THE BREAKER CAN BE
TRIPPED AT FULL SPEED.
10.5. GAG TOOL REMOVAL
To remove the gag tool, the closing spring must be
fully charged. If the spring charge indicator does
not show "CHARGED" in the window, manually
charge the spring until it does. Lift up and push in
on the gag tool to clear the détentes on the gag
tool from the slots in the closing spring guide.
While holding the gag tool up, remove it from the
opening. Close the gag hole cover. For safety, first
close the breaker by depressing the manual
"CLOSE" button and then depress the manual
"TRIP" button. All stored energy is now removed
from the breaker.
11. DIMENSIONAL CHECKS
With the breaker closed and the gag tool installed,
remove the front portion of the breaker top plate
before performing the following dimensional
checks:
11.1. PRIMARY CONTACT EROSION
In the closed position, the erosion disk (5, Fig. 21),
located below the operating rod insulator, is
aligned with a reference arm (4, Fig. 21) on new
interrupters. As contact erosion occurs, the erosion
disk will move upward from alignment with that
reference arm. When erosion reaches 1/8 inch, the
POWER/VAC VL interrupters should be replaced.
DO NOT READJUST THE ALIGNMENT OF THE
EROSION INDICATOR ARM EXCEPT WHEN
INSTALLING A NEW VACUUM INTERRUPTER.
11.2. SPRING WIPE
With the breaker closed and the closing spring
gagged, measure with a feeler gauge and record
the distance between the top of the wipe indicator
and the bottom of the erosion disk for each phase
(see Figure 33 Dimension W). Trip the breaker with
the closing spring gag tool still installed and
measure and record the distance between the wipe
indicator and erosion disk. Subtract the closed
position measurement from the open position
measurement. The result is the amount of wipe on
each individual pole. The wipe is to be greater than
0.075 inch. Adjustment is not required until wipe is
0.075 inch or less. If adjustment is required see
WIPE ADJUSTMENT in MECHANICAL ADJUST-
MENTS section.
The ML-18VL mechanism is furnished with very
low gradient wipe springs so that adjustment is not
a precision operation and considerable loss of wipe
can be tolerated without affecting performance.
11.3. CONTACT GAP
The method of measuring the contact gap is as
follows: With the breaker in the open position, the
closing springs charged, and the closing spring gag
tool installed, apply a piece of masking tape to the
surface of the operating rod insulator as shown in
Figure 27. Using a reference block, make a mark
on the tape near the top on all three poles. It is also
advisable to put a reference mark on the tape to
identify to which pole the tape is applied. Remove
the closing spring gag tool and close the breaker.
Using the same procedure as above, re-mark the
tape. This new mark will be near the bottom of the
tape. Trip the breaker, remove the tapes and re-
apply them to a flat surface. Measure the distance
between the two lines. A caliper will give an
accurate reading of the contact gap, Dimension G.