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Rockwell Automation Publication 2100-IN012G-EN-P - August 2016
Chapter 9
Maintenance
The factory-made power bus connections are tightened by a computer-
controlled torquing system. The following connections do not require
re-torquing, vertical to horizontal bus connections and power
conductor to horizontal bus connections. These factory-made
connections do not require servicing for the life of the MCC.
5. Periodically clean or replace the air filters depending on the
environmental conditions.
6. Check for the proper function and freedom of movement (no sticking
or binding) for the disconnect handle operating and defeater
mechanisms.
7. Replace broken, deformed, malfunctioning, or badly worn parts or
assemblies.
8. Inspect unit bus-stab connections for wear or corrosion.
Wear and/or corrosion can increase resistance and cause an increased
temperature of the contact point, leading to failure. Replace bus stabs if
wear or corrosion is excessive. Lubricate bus stabs with NO-OX-ID
grease (catalog number 2100H-N18 or 2100H-N18T) before installing
the unit into the section.
9. Inspect current carrying parts such as fuse clips, knife blades of
disconnects, and line and load terminals of devices for discoloration,
corrosion, or other signs of wear or possible failure.
10. Check locking or interlocking devices for proper working condition.
11. Adjust, repair, or replace any device if necessary.
ATTENTION:
When working on or near energized electrical equipment,
follow established electrical safety-related work practices. Refer to NFPA 70E
Standard for Electrical Safety in the Workplace.
To prevent injury or death to personnel lubricating disconnect switch contacts,
make sure the MCC power sources are disconnected and the respective
disconnects are locked in the OFF/O position. For plug-in units, remove the unit
from the MCC.
To prevent personal injury or damage to equipment, make sure that the unit
handle operator is in the OFF/O position before removing the unit.