ABB VD4 Series Instruction manual - page 15
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5
Maintenance
5.1
General
Maintenance serves to preserve trouble-free
operation and achieve the longest possible wor-
king life of the switchgear. In accordance with
DIN 31051 and/or IEC 61208, it comprises the
following closely related activities:
Inspection: Determination of the actual condition.
Servicing: Measures to preserve the specified
condition.
Repairs:
Measures to restore the specified
condition.
Vacuum circuit-breakers are characterized by their
simple and robust construction. They have a long life
expectancy. Their operating mechanisms have a low
maintenance requirement, and the interrupters are
maintenance-free during their working life. There is
no adverse effect on the vacuum, even from frequent
switching of operating and short-circuit currents.
The servicing intervals and scope are determined
byenvironmentalinfluences,theswitchingsequen-
ces and number of short-circuit breaking operati-
ons.
Note:
The following must be observed for all maintenance
work:
• Therelevantspecificationsinsection1.2.2
• Notesonsafetyatworkinsection4.1
• Standards and specifications in the country of
installation.
Maintenance work may only be performed by fully
trained personnel, observing all the relevant safety
regulations. It is recommended that ABB after-sales
service personnel should be called in, at least du-
ring the performance of servicing and repair work.
While the work is in progress, all supply voltage
sources must also be disconnected and secured
to prevent reconnection.
Note:
In order to prevent accidents (particularly injury
to hands!) extreme care should be taken during
all repair work on the operating mechanism,
especially with front plate removed.
The spiral spring in the spring energy storage me-
chanism, for instance, retains a basic tension which
is independent of the charging and discharging
processes during switching, so as to ensure correct
function. This spring energy can be inadvertently
released if work is performed incorrectly on the
spring mechanism!
Together with this instruction manual, it is essential
to consult manual BA 359, Vacuum circuit-breaker
type VD4, high current.
The service life data fundamentally apply to all
components which are not directly influenced by
the operator.
Components operated manually (movement of the
withdrawable part, etc.) may deviate, depending on
how they are handled.
If necessary, further details can be taken from the
technical documentation for the switchgear (inclu-
ding, for example, any agreed special operating
conditions).
5.2
Inspection and functional testing
5.2.1 General
• Theproperconditionoftheswitchingdeviceis
to be verified by regular inspection.
• Thechecksaretobeperformedinaccordance
with BGV A2 standards.
• Inspection at fixed intervals may be waived if
the switchgear is permanently monitored by a
qualified personnel.
• The checks first and foremost comprise visual
examination for contamination, corrosion, moi-
sture and discharge phenomena.
• Inunusualoperatingconditions(includingadverse
climatic conditions) and/or special environmental
pollutions (e.g. heavy contamination and ag-
gressive atmosphere), inspection may also be
necessary at shorter intervals.
• Visualcheckingoftheisolatingcontactsystem.
We recommend to turn alternately the contact
system in order to clean the inner contact points
of the contact system.
The contact points should be cleaned if signs of
unperminable overheating (discoloured surface)
are visible (see section Repairs)
• Ifirregularconditionsaredetected,thencorre-
sponding repair measures should be initiated.
For details of inspection and functional testing,
see the relevant sections of manual BA 359.
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