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5.2. Maintenance
Vmax circuit-breakers are designed for a minimum amount
of maintenance. Circuit-breakers in a clean, non-corrosive
environment require only annual inspection. Dusty or corrosive
environments require inspection more often at the discretion
of the user. Following each interrupted fault inspection is
required.
do not
work on an energized circuit-breaker.
do not
work on a circuit-breaker unless all of the
components are disconnected by means of a visible break
and securely grounded.
do not
work on a circuit-breaker with power supplied to the
secondary control circuit.
do not
defeat safety interlocks. This may result in bodily
injury, death and/or equipment damage.
do not
work on a closed circuit-breaker.
do not
work on a circuit-breaker with charged energy.
(springs)
do not
use a circuit-breaker by itself as the sole means of
isolating a high voltage circuit.
do not
leave a circuit-breaker in an intermediate position in
a cell. Always have the circuit-breaker in the Disconnect or
Connect position.
5.2.1. general
Vacuum circuit-breakers are characterised by simple, sturdy
construction and long life.
The drive is maintenance-free for its whole operating life and
only requires functional inspections.
The vacuum interrupters are maintenance-free for their whole
operating life.
Vacuum interruption does not produce harmful effects even
when there are frequent trips at the rated and short-circuit
current.
The servicing interventions and their aim depend on the
environmental conditions, on the sequence of operations and
on the trips under short-circuit.
note
For maintenance work, respect the following Standards:
– the relative specifications indicated in the “Standards and
Specifications” chapter;
– regulations for safety in the workplace indicated in the
“Putting into service and operations” chapter;
– regulations and specifications of the country where the
apparatus is installed.
The maintenance operations can only be carried out by
trained personnel who respect all the safety regulations.
Furthermore, is recommended that Abb service personnel
should be called in, at least to check the service
performances, and for any repair work.
During maintenance work, turn the power supply off and put
the apparatus under safe conditions.
bEFORE CARRyING OuT ANy
OPERATIONS, ALwAyS MAkE SuRE
THAT THE CIRCuIT-bREAkER IS OPEN,
THE SPRINGS ARE DISCHARGED AND
IT IS NOT SuPPLIED (MEDIuM VOLTAGE
CIRCuIT AND AuXILIARy CIRCuITS).
CAUTION
