GE Industrial Solutions PowerVac 5kV VL PV VL 4.16-250-0 - Manual (Page 60)

60
Care should be exercised in the maintenance
and checking procedures that accidental trip-
ping or operation of the protective devices is
not initiated.
The equipment and connections should be given
the following overall maintenance at least an-
nually.
1. Thoroughly clean the equipment, remov-
ing all dust and other accumulations. Wipe
clean the buses and supports with a clean
cloth and denatured alcohol. Do not use
solvents. Inspect the buses and connec-
tions carefully for evidence of overheating
or weakening of the insulation.
2. Measure the resistance to ground and be-
tween phases of the insulation of buses
and connections. Since definite limits can-
not be given for satisfactory insulation re-
sistance values, a record must be kept of
the reading. Weakening of the insulation
from one maintenance period to the next
can be recognized from the comparison of
the recorded readings. The readings
should be taken under similar conditions
each time, and the recordings should be
adjusted to include the temperature and hu-
midity.
PowerVac ® 5kV Vertical Lift
Chapter 14. Stationary Cubicle Subassembly
Hi-potential tests are not required, but if it
seems advisable, based on the insulation
resistance tests or after repairs, the test
voltage should not exceed 14kV AC, 60 Hz.
These voltages are 75% of the factory test
voltages and are in accordance with ANSI
standards.
Potential transformers and control power
transformers must be disconnected during
high voltage testing.
3. Clean elevating mechanism and lubricate.
4. Check primary disconnecting device con-
tacts for signs of abnormal wear or over-
heating. Clean contacts with de-natured
alcohol.
Discoloration of the silvered surfaces is not
ordinarily harmful unless atmospheric con-
ditions cause deposits, such as sulfides,
on the contacts. If necessary, the deposits
can be removed with a good grade of sil-
ver polish.
Before inserting the breaker, apply a thin
coat of 0282A2048P009 lubricant, to the
breaker studs for lubrication.
5. Check tightness and continuity of all con-
trol connections and wiring.
6. If the equipment is equipped with heaters,
check to see that all heaters are energized
and operating.