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DEH-41473
Bus Area
DANGER: Electrical arc flash hazard. Personal
protection equipment required. Turn off power to the
equipment before working inside.
WARNING: De-energize the equipment completely
before doing maintenance work on any devices,
connections, bus work, breaker or feeder cable
compartments. This includes de-energizing any
connections to outside primary or secondary sources, such
as transformers, tie lines, etc.
WARNING: The rear compartment door(s) must be
closed and bolted to maintain the integrity of the arc
resistant enclosure. If provided with IR viewing windows, the
IR window cover must be closed and secured to maintain
the integrity of the arc resistant enclosure.
Inspect and check the bus area as follows:
1.
Inspect the buses and connections carefully for
evidence of overheating or weakening of the
insulating supports. If bus insulation is present,
remove the molded covers over the main bus
connection to expose joints for inspection.
2.
Check all connection bolts in the bus compartment
and all bracing bolts for tightness. See the Table A-1
in Appendix – Torque Values.
3.
Vacuum and, with a clean rag, wipe the buses and
supports.
4.
Visually inspect the insulation on the bars that run
from the breaker studs through the bus structure to
the cable area.
5.
After cleaning, megger and record the resistance to
ground and between phases of all insulated bars and
all buses and connections. Disconnect all control
circuits before checking resistance. Do not use over
a 1,500-volt megger. Since definite limits cannot be
given for satisfactory insulation resistance values, a
record must be kept of the readings.
Weakening of the insulation from one maintenance period to
the next can be recognized from the recorded readings. The
readings should be taken under similar conditions each time,
if possible, and the record should include the ambient
temperature and humidity.
Circuit Breaker Lifting Mechanism
Under normal conditions, no special maintenance procedures
or lubrication is required for this device. If the cable is
abraded under any condition, it should be inspected for
broken strands or other damage and replaced if necessary.
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Courtesy of NationalSwitchgear.com
AKD-20 AR / Entellisys AR Low-voltage Switchgear
Section 10. Maintaining the Switchgear
Overall Switchgear
Make the following checks on the complete switchgear
equipment.
•
Clean and inspect all painted surfaces and retouch
where necessary.
•
Check to see that all anchor bolts and other
structural bolts are tight.
•
Check that all breaker and instrument compartment
door latches operate properly.
•
If the switchgear is equipped with heaters, check to
see that all heaters are energized and operating.
•
For exterior vent openings in equipment furnished
with air filters, the foam filter elements should be
removed and washed in warm soapy water, rinsed,
and reassembled at least annually. Elements should
be inspected before re-assembly and replaced if any
signs of deterioration are evident.
Paint Refinishing
Indoor switchgear is finished with ANSI-61 gray acrylic
enamel paint (PPG W42713, GE part number 21525032650).
To refinish damaged areas, remove all loose paint, rust, scale,
oil or grease. Sand any scratches smooth using 220 grit
paper or finer.
Apply a coat of good acrylic enamel primer (Sherman-
Williams E61 A 60,-GE part number 21525025200) with a
viscosity of approximately 24-32 seconds using a #2 Zahn
cup. Reduce with D5B9 Xylol (GE part number 21525038000)
if needed. Air dry the primer for a minimum of 30 minutes,
then apply the finish color coat of acrylic enamel. The top
coat should be applied within 24 hours for best adhesion.
If the area is to be spray-coated, thin the acrylic enamel with
D5B9 Xylol (GE part number 21525038000). This thinning
should only be necessary if the paint was received in a five
gallon drum or more. The recommended viscosity for the
W42713 topcoat should be 24-32 seconds with a #2 Zahn
cup. The curing schedule for PPG W42713 is dust free in 5
minutes, touch in 30 minutes, handle in 60 minutes, full cure
in 7 days. Both the primer (Sherwin-Williams E61 A 60) and
paint (PPG W42713) should be applied only when temperature
is above 55 degrees Fahrenheit.
Application of special paint will be per the manufacturer's
Product Data Sheet which includes instructions on thinning
and application.
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