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SIVACON S4 - ALPHA
Maintenance cycle
SENTRON 3WL Air circuit breakers
Maintenance
1)
Contact assemblies need to be changed
according with their conditions, but at
least after:
- 10.000 operations in FS 1 and FS 2
- 5.000 operations in FS 3
• A indicated in SENTRON 3WL operating
instructions: the switchgear operator
has to be determine inspection intervals
depending on the breaker application
conditions:
- min. 1 per annum
- after interruption of heavy loads
- after trips by the overcurrent release
(trip unit)
- down stream connected non-automatic
circuit breakers have to be inspected also.
During the inspection and/or after 1.000
switching operations, the following items
must be examined: (max. operations see
catalogue)
- arc-chutes and contact systems
- electrical and mechanical functionaliy
of the breaker
- mechanical on/off-functionality
- main and auxiliary circuits, function
and connecting quality
- plausibility control of trip unit settings
and corrections, if necessary.
• If the breaker endurance is exhausted,
then the breaker and old spare parts
are to be disposed of, according
to the effective legal regulations.
• Drawing out guide frames with arc-
chute covers installed, have to be
replaced after no more than three
schort-circuit interruptions of the
circuit-breaker.
• The arc chutes and the contact system
must be replaced depending upon
their condition, but latest after 10,000
switching operations.
• Depending on the circuit-breaker stress
it may also be necessary to replace the
operating system after 10,000 switching
operations.
SENTRON circuit breakers
Maintenance
• It is not possible to replace the power
contacts on any switch in Sentron family
• We recommend replacing the switch
after an intervention for a short circuit
corresponding to its I
cu
value
• We recommend replacing the switch
when it has reached the end of its
mechanical service life
• Whenever the system is stopped for
ordinary/extraordinary maintenance
works, it is advisable to check the
tightening of all power and auxiliary
terminals
• Checking and tightening the
mechanical fixed screws of the switch to
its assembly plate.
For SENTRON 3VA circuit breaker refer to
manual available in 3VA Manual
2)
.
We recommend performing these
operations at least every six/twelve
months, also as function of site
conditions.
(For instance, panels or machines
exposed to vibrations).
1)
For the SENTRON 3WL air circuit breaker maintenance
it is necessary to refer to the SENTRON 3WL operating
instructions available in
http://support.automation.siemens.com
2)
Manual available in
http://support.automation.siemens.com
go to the heading SENTRON 3VA
ITA
ENG
