1VAL050503-MB Rev B Replaces (1VAL057485-MB Rev. C) Oct 2013
23
General
The vacuum circuit-breakers are characterized by simple, sturdy construction and a long life. The operating mecha-
nism requires maintenance and functional inspections to reach the expected operating life. The vacuum interrupters
are maintenance free for their whole operating life. Vacuum interruption does not produce any harmful effects even
when there are frequent interruptions at the rated and short circuit current. The interventions during service and their
aim are determined by the ambient conditions, by the sequence of operations and by the short-circuit interruptions.
The maintenance operations must only be carried out by trained personnel and who follow all the safety regulations.
Furthermore, it is advisable to call on ABB personnel, at least in cases for checking the performances in service and
for repairs. Cut the power supply off and put the apparatus under safe conditions during the maintenance operations.
Before carrying out any operations, check that the circuit breaker is open, with the spring discharged and that it is not
supplied power.
Operating life expectancy
The operating life expectancy for the ADVAC circuit-breakers is as follows:
Vacuum interrupters: up to 30,000 operations, according to their type .
Switching device, actuator and transmission system: up to 30,000 operations, under normal operating conditions, ac-
cording to the type of circuit breaker and with regular maintenance.
With operations correctly executed it is possible to carry out up to1000 racking-out/in operations (as prescribed in the
ANSI C37.06 Standards)
.The data regarding the operating life are basically applicable to all the components which cannot be directly affected
by operator activity. The manually operated components (moving parts of isolatable parts, etc.) can vary their due to
their behavior.
Inspections and functionality tests
Check the conditions of the interruption devices with regular inspections.
Inspection at fixed intervals can be avoided when the apparatus is permanently under the control of qualified person-
nel.
The checks must, first of all, include visual inspection to check for any contamination, traces of corrosion or electrical
discharge phenomena.
Carry out more frequent inspections when there are unusual operating conditions (including severe climatic condi-
tions) and in the case of environmental pollution (e.g. / high level of contamination or an atmosphere with aggressive
agents).
Visual inspection of the isolating contacts. It is recommended to turn the contact system alternately in order to keep
the internal surface of the contact areas clean. The contact areas must be cleaned when there are signs of overheat-
ing (discolored surface) .
In the case of abnormal conditions, take suitable overhauling measures .
MAINTENANCE