45
PowerVac
®
5kV Vertical Lift
Chapter 12. Repair and Replacement
12-3 Primary Disconnect
Bushings
The primary disconnect bushing assemblies
should not be removed. Alignment of these
items is critical to the function of the vertical lift
equipment. If removal of these bushings is
required, contact your local GE office for the
location of a GE Authorized Service Center that
can replace them.
12-4 Mechanism
Pin Retaining Rings – These rings are widely
used in the ML-19 mechanism to retain pins.
They can be installed and removed with a pair
of standard pliers. Reuse is not recommended.
To remove, slowly squeeze the removal ears to
open the ring. To install, position ring in the
pin groove and squeeze the installation ears
closed, leaving no more than 1/16 inch gap be-
tween the ears. Retaining rings can be obtained
from your local GE Sales office by ordering part
number 0282A2015G001.
12-5 Control Switches
Control switches may be removed from their
mounting brackets by disconnecting the wires
and removing the mounting hardware. When
replacing the switches, check that the correct
type, normally open or normally closed, is used.
Reinstall, wire, and adjust per DIMENSIONAL
CHECKS - CONTROL SWITCH ADJUSTMENT.
12-6 Trip Coil Replacement
TOOLS REQUIRED
1/8" Allen wrench
Needle nose pliers
7/16" Socket wrench
7/16" Box/combination wrench
1/4" Square drive ratchet
1/4" Square 3" extension
Loctite #271 or equivalent
Perform the operation in the following sequence:
Reference Figure 44
1.
Charge closing spring and install gag tool.
2.
Depress the close and then the trip but-
tons.
3.
Pump the manual close handle 3 - 4 times.
4.
With the 5/16" Allen wrench, remove the
pivot bolt (Figure 49) on the closing spring
(Figure 49, Item 3).
5.
Remove the closing spring.
6.
Disconnect the trip linkage tension spring
(Figure 44, Item 4).
3.
Remove interrupter assembly fasteners (8);
four on the upper standoff and four on the
lower. Remove the old assembly and in-
stall the new assembly.
4.
Install the new assembly. Screw the oper-
ating rod insulator up to mate with the base
of the interrupter rod. Install coupling
clamp. Tighten coupling clamp cap screws,
then loosen them 1-2 turns.
a.
With continuity indicator across the con-
tacts, back off the operating rod until the
contacts separate, (continuity indicator
off).
b.
Advance operating rod until contacts
touch, (continuity indicator on).
c.
Advance operating rod two and one-half
(2-1/2) additional turns.
d.
Tighten lock nut to 40-50 foot pounds
and the coupling clamp cap screws to
8-10 foot pounds.
e.
Check wipe - must be 0.12 - 0.18 inch
(set all three phases before measuring).
It is not necessary that all three poles
have the same wipe measurement as
long as all three poles fall within the
specified limits.
f.
Check gap - must be 0.48 - 0.60 inch.
Adjust if needed per CONTACT GAP
ADJUSTMENT in MECHANICAL AD-
JUSTMENT (Chapter 11-3).
5.
After the interrupter assembly is installed,
check the erosion indicator. If the erosion
indicator does not line up to the mark, ad-
just indicator (Figure 23).
6.
Perform the VACUUM INTERRUPTER IN-
TEGRITY TEST as described in ELECTRI-
CAL CHECKS (Chapter 9-4).
CAUTION:
PRIMARY DISCONNECT WIPE
CAN ONLY BE CHECKED WHEN THE
SWITCHEAR IS DE-ENERGIZED.
