Masterpact ® circuit breaker
advantages
drawout circuit breaker
design
•
the drawout assembly mechanism allows
the circuit breaker to be racked in 4 positions
(connected, test, disconnected and withdrawn).
•
the closing and opening push buttons, the
racking handle and racking mechanism are
accessible through the front door cutout.
Disconnecting the circuit breaker will be
therefore possible without opening the door
and accessing live parts. Safety shutters can
be provided for protection from live parts
when the circuit breaker is removed.
connected position
test position
disconnected position
MP1 025A.O
true 2-step stored energy
mechanism
The closing time is less than 5 cycles.
The circuit breaker is operated via a stored
energy mechanism which can be manually
or motor charged. Closing and opening
operations can be initiated either from the
local push buttons on the circuit breaker
front face, or by remote control.
0-C-0 cycle is possible without recharging.
field-installable accessories
•
as the installation develops and changes
the circuit breaker can develop and change
with it. Most accessories are field-installable,
without losing the UL Listing mark, without
any adjustment and with only the aid of a
screwdriver.
•
the uniform design of the circuit breaker
line allows these accessories to be common
for the whole line.
front connection of
secondary circuits
All accessory terminals are located on a
connecting block which is accessible from
the front even with the circuit breaker in the
test or disconnected position. This is
particularly useful for field inspection and
modification.
designed for no
maintenance ...
The circuit breaker has fewer parts (by a
factor of at least 5) than conventional circuit
breakers while performing the same
functions. This leads to greatly enhanced
reliability and reduction in maintenance.
Under normal operating conditions, given by
standards and controlled by tests, the circuit
breaker does not require maintenance.
. . . but exceeds the standard
with an easy and reduced
maintenance
It is easy to remove the arc chutes and
visually inspect the contacts and wear
indicator. The operation counter (spring
charging motor option) can also indicate
when inspections and possible maintenance
should be done.
After operating conditions exceeding those
given by standards, it is possible to extend
the circuit breaker life by:
•
replacement of arc chutes and spring
charging motor by the user.
•
replacement of main contacts by an after
sale service team.
Note:
see page 37 for additional information.
MP1 028A.O
3
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