Maintenance; Inspection And Functional Testing - ABB VD4 Installation And Service Instructions Manual

D I S T R I B U T I O N S O L U T I O N S
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7. Maintenance

Maintenance serves to ensure trouble-free
operation and achieve the longest possible working
life of the switchgear.
In accordance with DIN 31051 / IEC 61208 / IEC
62271-1 it comprises the following closely related
activities:
Inspection:
Servicing:
Repair:
7.1
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 by
environmental influences, the switching sequen ces
and number of short-circuit breaking operations.
Note:
The following must be observed for all maintenance
work:
• The relevant specifications in section 1.2.2
• Notes on safety at work in section 6.1
• 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 during
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.
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 store, 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!
Determination of the actual condition
Preservation of a functional condition
Measures to restore the functional
condition.
General
Note:
7.1.1 Service life
Typical life expectancies for VD4 fixed/P 63kA
circuit breakers:
• The maintenance-free vacuum interrupters up to
10,000 operating cycles
• The breaker itself, depending on presupposing
carefully performed inspection and servicing work
and normal operating conditions, up to 2000
operating cycles.
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.
7.2 Inspection and functional
testing
7.2.1 Switching devices in general
• The proper condition of the switching device is to
be verified by regular inspection.
• The checks are to be performed in accordance
with BGV A3 standard. If further standards exist in
the country of installation they shall be considered
in the checks.
• 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,
moisture and discharge phenomena.
• In unusual operating conditions (including adverse
climatic conditions) and/or special environmental
pollutions (e.g. heavy contamination and
aggressive atmosphere), inspection may also be
necessary at shorter intervals.
• If an incorrect condition is found, appropriate
servicing measures are to be initiated.
7.2.2 Stored-energy spring mechanism
Functional testing of the operating mechanism is to
be performed:
• after 2000 operating cycles or 5 years or
• during servicing work.
Prior to functional testing, switch the breaker off
and isolate the outgoing feeder.
Note:
Isolate and secure the working area in accordance
with the safety regulations specified by DIN VDE/
IEC.
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