Siemens UL489 Quick Start Manual page 6

Requirement for "Ready to Close" or "OK"
UL489 and UL1066 WL Low Voltage Air Circuit Breakers
In order to close the WL circuit breaker, the OK indicator must be present as shown
here. The circuit breaker will not close without this condition being met. Check the
following items if this can not be achieved.
1. The circuit breaker contacts must be open.
2. The trip unit rating plug must be inserted. If a rating plug with a higher current
than the maximum permissible circuit breaker rated continuous current is
plugged in, the electronic system of the trip unit recognizes this error and signals
it with a flashing T.U. ERROR indicator.
3. The mechanical RESET at the top left corner of the trip unit assembly must be
pushed in all the way. This RESET can also be electrically operated if equipped
with the remote reset solenoid for the trip indicator/bell alarm.
4. If the circuit breaker is a draw-out type it should be racked into the test or
connected position to apply secondary and control voltages to the circuit breaker.
NOTE: The draw-out breaker can also be operated in the disconnected position
without secondary and control voltages if the breaker is not equipped with an
undervoltage release.
5. For low voltage switchgear applications and other custom panels with a cubicle
door interlock mechanism, the cubicle door must be closed.
6. The racking handle must be completely inserted into the circuit breaker.
7. The storage springs must be charged either manually or electrically. If manually
charged, the charging handle must be completely stowed into the breaker frame.
If the handle is loose or does not return to its stowed position after the final (9
stroke, service is required.
8. The undervoltage release must be energized. Control voltage to the
undervoltage release must be within the acceptable range.
9. Confirm that the shunt trip(s) are not energized. Verify control logic to assure
that no control voltage is applied to the shunt trip coil(s).
10. Verify that terminals X5.13 and X5.14 are shorted if an undervoltage release is
installed in the circuit breaker (no EMERGENCY OPEN).
11. Verify that the trip unit interlock is functioning correctly. The metal tab that
protrudes from the top right of the trip unit must not be bent or broken. The tab
must engage the metal interlock assembly (breaker cover must be removed to
inspect).
12. Before closing the breaker, verify that any electrical or mechanical interlocks are
disabled that will prevent electrical or mechanical closing. Also disable any
locking devices that may prevent closing.
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