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.Table feasible mechanical interlocks between two three circuit-breakers
Type of
interlocks
Number of
circuit-breakers
Type circuit-breaker Possible interlocks
A TWO normal power supply unit
and emergency unit
the first circuit-breaker can closed only if
the second (emergency) breaker open
B THREE two normal power supply units and
an emergency unit
the first and third circuit-breakers can be
closed only the second (emergency)
breaker open.3 parts
The spare parts available are:
- Shields and front escutcheon plate
- Opening solenoid for the PR122/DC-PR123/DC overcurrent release
- Arcing chamber
- Closing springs
- Clamp-type isolating contact for fixed part the withdrawable circuit-breaker
- Sliding earth contact (for withdrawable version)
- Fixed part shutters
- Operating mechanism
- Transparent protection for PR122/DC and PR123/DC releases
- SACE PR030/B power supply unit
- Tool case
- Front escutcheon plate for Ronis-type key lock
For further details, ask for the ABB SACE spare parts catalogue. Three supplies
(generators transformers) the same
busbar for which parallel operation is
not allowed
only one the three circuit-breakers can
be closed
10.
The two half-busbars can supplied
by single transformer (bus-tie closed)
or simultaneously both
(bus-tie open)
one two circuit-breakers out three can
be closed the same time
D THREE unit supplies single
closed circuit-breaker.
Model 3447 Apparatus Emax cale
D oc-N 1SDH000635R0002
Page No. The latter can closed
only the first and third are open
C THREE unit supplies and bus-tie
