Maintenance; Service-Life; Inspection And Functional Testing; Switching Devices In General - ABB VD4X Instruction Manual

24 V D 4 X I N S T R U C T I O N M A N U A L
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Maintenance

Maintenance serves to ensure trouble-free
operation and achieve the longest possible
working life of the switchgear. In accordance
with DIN 31051, IEC 62271-1 it comprises the
following closely related activities:
Inspection: Determination of the actual
Servicing: Preservation of a functional
Repair: Measures to restore the functional
5.1 5.1 General
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
sequences and number of short-circuit breaking
operations.
Note
The following must be observed for all
maintenance work:
• The relevant specifications in section
"Standards and specifications"
• Notes on safety at work in section
"Commissioning / Operation"
• 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.
condition
condition
condition
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 mechanism, 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!

5.1.1 Service-life

Typical life-expectancies for VD4X circuit-breakers.
Vacuum interrupter
Up to 30,000 switching cycles (see section
"Permissible numbers of switching cycles" page 9)
Device
Up to 30,000 operating cycles, depending on
switch type and assuming conscientiously
performed inspection and maintenance work
and normal operating conditions.

5.2 Inspection and functional testing

5.2.1 Switching devices in general

• The proper condition of the switching device
is to be verified by regular inspection
• 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 and
moisture
• 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