IB 6.2.11.1-1C
Page 16
ABB
1. Rack the circuit breaker to the TEST position. Make
sure the closing springs are charged.
2. Operate the local (if installed) or remote electrical
close push button as applicable to close the circuit
breaker. This will confirm operation of the close coil.
3. While maintaining the close signal, trip the circuit
breaker with the shunt trip. The Solid State Control
Device (SSCD) should prevent the reclosing of the
circuit breaker until the close signal is removed and
then re-applied. SSCD replacement may be required if
it does not perform as indicated.
4. During the previous test, electrical operation of the
shunt trip and the spring charging motor is confirmed.
Malfunction of either requires repair or replacement.
Insulation Structures
Polyester glass insulation and base molding
assemblies should be checked for breakage, cracking,
or burn marks from normal operation and especially
following fault interruption. Dust, soot and dirt should
be removed by wiping with a lint-free cloth. Even
though some greasy dirt may be present, THE USE OF
ANY TYPE OF SOLVENT CLEANER IS STRICTLY
FORBIDDEN.
To remove persistent contamination, apply a mild
detergent and wipe with a water-moistened cloth, then
dry thoroughly.
If environmental conditions fall in the severe category
as defined by ANSI C37.13, Paragraph 10.6, additional
measures may be necessary to avoid breaker
misoperation and further contamination.
ADJUSTMENTS
The adjustments detailed below should only be
performed when the periodic maintenance inspection
verifies that the close coil, SSCD, shunt trip, or tripper
latch require them. Because these devices may
incorporate locking hardware intended to hold the
factory adjustments, malfunction of one of the items
listed above should be the only reason for making any
adjustment; the locking hardware will become
ineffective when adjustments are made at each
maintenance period regardless of whether they are
needed or not.
Operating experience indicates that the contact gap
adjustment is the only one normally required during the
periodic maintenance interval. When contacts are
replaced or abraded during cleaning, contact gap
adjustment is mandatory.
FOR SAFETY: See SAFETY NOTES in
MAINTENANCE section.
NOTE: The operating mechanism must be operated
slowly, as described in section SLOW CLOSE
PROCEDURE, when performing any adjustment
requiring contact movement.
In order to close the circuit breaker, the racking
mechanism must be turned to a position such that the
racking shutter is closed when the racking crank is
removed.
SLOW CLOSE PROCEDURE
NOTE: The circuit breaker should be clamped down
during the slow close procedure to keep it from tilting or
moving.
Manually Operated Circuit Breakers
Refer to Figure 5 unless otherwise noted.
1. Loosely install 1/4 inch diameter pins or machine
screws in each of the two spring guards located under
the breaker (See Fig. 6).
2. Insert a screwdriver or rod through the hole in the
escutcheon box and mechanism housing assembly
(right-hand side when facing the front of the circuit
breaker).
3. Using the top of the hole as the fulcrum and the
screwdriver or rod as the lever, depress the hold-up
latch at "A" and, at the same time, pull the operating
handle downward to slowly close the circuit breaker
contacts.
4. Remove the two 1/4 inch diameter pins or machine
screws installed in Step 1 after the slow close operation
is complete.
Electrically Operated Circuit Breakers
NOTE: The charging cranks must be reset (see steps
8, 9, and 10 below) after the last slow close operation,
or future electrical operation will be impossible.
Refer to Figure 7 unless otherwise noted.
1. The closing springs must be charged; see spring
charge indicator.
2. Insert a screwdriver or rod through the hole in the
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