GE Industrial Solutions Power Break II Draw-out 800-4000 Amp Frames - Manual (Page 10)

Power Break® II Devices
Draw-Out Device Installation
6
Maintenance Procedures
A regular maintenance schedule should be established to
obtain the best service and reliability. Plant operating and
local conditions dictate the frequency of inspections
required.
A permanent record should be kept of all maintenance
work. It will be a valuable reference for subsequent
maintenance work and station operation. Records should
include reports of tests performed, condition of
equipment, and repairs and adjustments.
Maintenance employees must follow all recognized safety
practices, such as those contained in the National
Electrical Safety Code and in company or other safety
regulations. Solid insulation surrounding an energized
conductor in power apparatus must never be relied upon
to provide protection to personnel.
Draw-out structure and connections should be given the
following overall maintenance at least annually.
Maintenance frequency depends on the severity of service
and atmospheric conditions. Equipment subject to highly
repetitive operation may require more frequent
maintenance.
While some of these steps can be done with the device in
the tilt-out position, a complete check can only be made
after removing the device from the rails.
WARNING: Before attempting any work on draw-out
devices, ensure that all sources of power—primary and
secondary—have been de-energized.
AVERTISSEMENT: Avant de commencer toute
intervention sur des mécanismes débrochable, vérifier
que toutes les alimentations de puissance, à la fois
primaire et secondaire, sont coupées.
1. Thoroughly clean the equipment by removing all
dust and other accumulations. Wipe or vacuum clean
the buses and supports. Do not use compressed air
for blowing out equipment.
2. Inspect buses and/or terminal lug connections for
signs of overheating or weakening of insulating
supports. Check indicating devices and mechanical
and key interlocks for proper functioning. Lubricate
all moving and rubbing parts with a suitable
lubricant, such as Mobil 28 red grease.
3. Check primary and secondary disconnecting surfaces
for signs of abnormal wear or overheating. If
required, clean contacts with a suitable solvent.
Discoloration of silvered surfaces is not harmful
unless atmospheric conditions cause deposits, such as
sulfides, on the contact surfaces.
4. Check to see that all anchor bolts and structure bolts
are tight. Inspect all cable or bus connections for
signs of overheating and tighten all loose
connections. Check that all secondary connections
are secure and all control wiring is intact.
5. After cleaning with the device removed, measure and
record resistances to ground and between phases of
insulation on buses and connections. Since definite
limits cannot be given for satisfactory resistance
values, keep a record of resistance readings so that
weakening of insulation from one maintenance
period to the next can be recognized by comparing
readings. Readings should be taken under similar
conditions each time, if possible, and the record
should include temperature and humidity.
High potential tests are not required, but if it seems
advisable, based on insulation resistance tests or after
repairs, test voltage should not exceed 75% of the
factory test voltage, which is two times the rating plus
1000 volts.
6. Operate each device in the TEST position to ensure
proper functioning. This is particularly important for
devices that normally remain in either the opened or
closed positions for long periods.
7. When the equipment is subject to unusual
conditions, such as contaminating fumes and
excessive moisture, schedule maintenance at more
frequent intervals. In this case, this procedure may
not be sufficient and additional precautions may be
necessary to protect the equipment.
Lubrication
All the areas subject to friction are liberally coated at the
factory with Mobil 28 red grease. If the contact surfaces,
the device power screw, and the interlock pin are cleaned
during maintenance, coat the primary disconnect contact
surfaces, the threads of the nut or screw, and the interlock
pin with Mobil 28.