ABB GCE7002270R0107, Инструкция по эксплуатации

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ABB Power Distribution 17
7
Maintenance
Maintenance serves to ensure trouble-free
operation and achive the longest possible
working life of the switchgear. In accordance with
DIN 31 051 / IEC 61208 it comprises the following
closely related activities:
Inspection: Determination of the actual condition
Servicing: Measures to maintain the specified
condition
Repair: Measures to restore the specified
condition.
7.1 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.
With carefully performed inspections and servicing
work, and under normal operating conditions, the
circuit-breakers, depending on the type, have a
service life of up to 20,000 operating cycles and
more.
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 Calor
Emag 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 auxiliary 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 50.7 removed.
The spiral spring in the spring energy strage
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!
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.
Under normal operating conditions, testing by a
qualified personnel is to be performed at least every
4 years (in accordance with VBG 4 standard).
In unusual operating conditions (including adverse
climatic conditions) and/or special environmental
pollutions (e.g. heavy contamination and aggressi-
ve atmosphere), inspection may also be necessary
at shorter intervals.
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.
If an incorrect condition is found, appropriate
servicing measures are to initiated.
7.2.2 Stored-energy spring mechanism
(Figures 7/1 and 7/2)
Functional testing of the operating mechanism is to
be performed:
• after 5000 operating cycles or
• during servicing work as set out in 7.2.1.
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.
Scope of functional testing:
• Perform several switching operations under no
load, above all with circuit-breakers seldom
operated in normal service.
• Switch off the charging motor (if fitted) and
discharge the spring mechanism by ON/OFF
switching operations.
• Examine visual the condition of the lubrication on
rotary bearings, sliding surfaces, etc.
• Check the proper mechanical/electrical se-
quence of the individual functions.
7.2.3 Breaker pole
No inspection of the breaker pole above and
beyond the stipulations of section 7.2.1 is
necessary.