Eaton Cutler-Hammer O & M Manual page 28

Page 22
Table 7.1 Periodic Maintenance Procedures
Step
a. Make transfer switch equipment safe for
inspection and/or maintenance.
b. Inspect structure area for safety hazards or
potential maintenance problems.
c. Inspect switching devices for dust, dirt, soot,
grease, moisture or corrosion.
d. Check for material integrity, uneven wear,
discoloration or loose hardware.
e. Check terminals and connectors for looseness
or signs of overheating.
f. Exercise the switching devices if they are
not often exercised while in operation. This
will permit wiping action by the contacts.
g. Inspect NEMA 3R filters for blockage or
contamination
h. Return transfer switch equipment to service.
Action
Disconnect line power from equipment being serviced by
opening next highest disconnect device. Make certain that
any accessory control power is switched off and logic plugs
disconnected.
Inspect area, especially where switching devices are
installed, for any safety hazards, including personnel
safety and fire hazards. Exposure to certain chemical
vapors can cause deterioration of electrical connections.
Inspect for accumulated dirt, loose hardware or physical
damage.
Examine primary insulation for evidence of cracking or
overheating. Overheating will show as discoloration,
melting, or blistering of conductor insulation, or as pitting
or melting of conductor surfaces due to arcing.
Inspect secondary control connections for damage, and
control wiring for insulation integrity.
Remove dust, dirt, soot, grease, moisture and corrosion
contamination from the surface of the switching device
using a dry soft lint-free cloth, dry soft bristle brush and
vacuum cleaner. Do not blow debris into circuit breaker or
nearby breaker structure. If contamination is found, look for
the source and fix the problem.
Severe material cracking will require replacement and
loose hardware will need to be tightened.
Overheating will show as discoloration, melting, or
blistering of conductor insulation.
Connections that do not have signs of looseness or
overheating should not be disturbed.
If a switching device is used for frequent switching during
normal operation, this step can be disregarded.
For NEMA 3R enclosed transfer switches with venting,
check that air filters are clean and uncompromised.
Replace filters as necessary (Cat. # TSAFFM)
Make certain all barriers are in place and doors closed.
Re-apply secondary and primary power.
IB01602002E
Effective 10/02