ABB VM1-T, Руководство пользователя

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VM1-T
- VACUUM CIRCUIT BREAKER 14
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7. Maintenance
Maintenance serves to preserve trouble-free
operation and achieve the longest possible working
life of the switchgear. In accordance with DIN 31 051
and IEC 61208, it comprises the following closely
related activities:
Inspection:
Determination of the actual condition
Servicing:
Preservation of a functional condition
Repair:
Measures to restore the functional condition
7.1 General
All vacuum circuit breakers are simple and robust in
design. They can be expected to have a long service
life. The vacuum is not even impaired by frequent
switching of operating and short-circuit currents.
The typical life expectancy of a VM1-T vacuum circuit
breaker is a function of:
• Maintenance-free, embedded vacuum interrupters
for up to 2,000 mechanical operating cycles.
• Maintenance-free control module with sensor
system and no auxiliary switches.
• Auxiliary switch for ON/OFF position signalling
(optional) for up to 2,000 operating cycles.
• Withdrawable assembly: With careful operation
and appropriately performed inspection work, up
to 1,000 movements can be performed.
See also IEC 60298.
Concerning detailed information about the
maintenance of the VM1-T circuit breaker please
contact the ABB service.
The service life data fundamentally refer to all
components which are not directly influenced by the
operator.
Deviations can occur for parts operated manually
(movement of the withdrawable part, etc.),
depending on how they are handled.
The servicing intervals and scope are determined by
the environmental influences, the switching
frequency and the 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, and if the work
permits, all supply voltage sources must also be
disconnected and secured to prevent re-connection.
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 1.1 removed.
The energy of the storage capacitor can be released
uncontrollably during incorrect handling!
Procedure for capacitor discharge:
1. Close the circuit breaker.
2. Turn off the supply voltage (m.c.b.).
3. Switch the circuit breaker in the following cycle
by pressing pushbuttons 3 and 4: OFF/ON/OFF.
On completion of this switching cycle the
“READY” lamp goes out, i.e. the circuitbreaker is
no longer ready for operation.
4. After approx. 12 minutes, the storage capacitors
have discharged to less than 15 V:
In addition to this instruction manual, it may be
necessary in individual cases to observe further
details in the technical documentation for the
switchgear (e.g. on special operating conditions
if stipulated).
7.2 Inspection and functional
testing
7.2.1 Circuit breaker in general
• Under normal operating conditions, inspection
within the stated number of operating cycles is
not necessary.
• Inspection may be necessary under exceptional
operating conditions (including adverse climatic
conditions) and/or particular environmental
stresses (e.g. serious contamination and
aggressive air).
• The inspection primarily comprises visual
examination for contamination, corrosion,
moisture and discharge phenomena on the high
voltage side.
• If an irregular condition is found, appropriate
maintenance work is to be initiated.