Page 6
Fig. 6
Handle Operation
The quick-make mechanism provides power to
overcome blowout forces that occur if the switch is
closed into a fault. These forces are not transmitted to
the operating handle since it is not rigidly connected to
the blades. The switch can therefore be safely closed
under short circuit conditions within its fault-close rating.
Load interruption is accomplished by flicker blades and
contact fingers located inside a DE-ION arc chute. On
opening the switch, the main blades open first and all
current is shunted through the spring-loaded flicker
blades. Further travel of the main blades cause the
flicker blades to snap out of their contact fingers. Arcing
takes place within the arc chutes between the contact
fingers and flicker blades.
4.3 Fuse Replacement
WARNING!
When accessing fuses, failure to assure that the
fuses are de-energized may result in equipment
damage, bodily injury, or death.
Make sure that all power sources are de-energized
before attempting to access the fuses.
When specified, the Type LBS switch is supplied with
Cutler-Hammer Type CLE or HLE current limiting power
fuses. Fuse puller, part number 6391D55G01, is
supplied with fuses rated 450 amps or less to aid in the
insertion and removal of the fuses. Instructions for
using the fuse puller are mounted on the inside of the
switch enclosure door. Fuses rated 600E to 1350E are
of the bolted type and are mounted in auxiliary
compartments.
Handle
Storage
Clips
SECTION 5 - MAINTENANCE
An LBS switch should be thoroughly inspected prior to
initial energizing. Every 100 operations or yearly
thereafter a cursory inspection to clean, lubricate, and
check for signs of wear and tear, damage, etc., is
recommended as described in section 5.1. If any
problems are discovered they should be corrected by
following procedures in sections 5.2 and 5.3. After 30
interruptions at the rated current or after the switch has
been exposed to fault currents, the switch should be
thoroughly inspected at the first opportunity. If the
switch has been moved or otherwise subjected to
mechanical strain, inspection procedures described in
Section 3 should be performed.
The rated mechanical life of the LBS is 500
operations.
5.1 Inspection Procedure
WARNING!
Failure to completely disconnect the switch from all
power sources prior to inspection or maintenance
may result in severe injury or death.
An LBS switch must be completely disconnected from
all power sources before performing inspection.
5.1.1 Main Blade and Flicker Blade Contact
Inspection
Check main blades and flicker blades for arc erosion.
Severely damaged
blade assemblies should be
replaced as described in Sections
5.3.1 and 5.3.2.
If flicker blades become rough from arc erosion, they
may be smoothed with a few light strokes of a fine file.
No attempt should be made to file out pit marks. Do not
use any abrasive material for cleaning. If questionable,
don’t file the flicker blades.
The main blade current carrying contact surfaces must
not be filed. Opening and closing the switch will keep
them clean. If main blade current carrying contact
surfaces are burned, they must be replaced.
5.1.2 Arc Chute Inspection
