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Manual source-changeover system
This is the most simple system. A human operator is required
and consequently, the transfer from the source S1 to the
source S2 is delayed.
A manual source-changeover system comprises two or three
manually controlled devices (circuit breakers or switch-
disconnectors) that are mechanically interlocked.
The interlocking system avoids simultaneous connection (even
transient) of the two sources.
Automatic source-changeover system
When a remote-operated source-changeover system is
combined with an automatic controller, the sources can be
controlled automatically according to a number of
programmed operating modes.
This solution provides optimum energy management:
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switching to a source S2 depending on any external
conditions
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management of sources
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regulation
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emergency source replacement, etc.
A communications function for dialogue with a supervisor is
available for the automatic controller.
Remote-operated source-changeover
system
This is themost commonly used system. No human intervention
is required.
The transfer from the S1 to the S2 source is managed
electrically.
A remote-operated source-changeover system is made up of
two or three devices linked by an electrical interlocking system
implemented in a number of manners.
Device control is backedupby amechanical interlocking system
that protects against the consequences of an electrical
malfunction and inhibits incorrect manual operation.
Functional system
Functional units
Source-changeover
Source-changeover
Compact / Masterpact
Presentation
See "Installation of source-changeover systems" pages D-89
and D-90.
See the catalogue dedicated to
Compact and Masterpact
source-changeover systems, catalogue
number: LVPED21122EN
3
1
2
To ensure the supply
of energy at all times,
certain electrical
installations are
connected to two
sources:
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the normal source
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the replacement source that steps in
to supply the installation if the
normal source is not available.
A mechanical and/or electrical
interlocking system between two
Compact or Masterpact switch-
disconnectors or circuit breakers (or a
mixture) avoids simultaneous
connection of the two sources during
switching.
The source-changeover systemcan be:
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manual when the devices are
mechanically interlocked
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remote operated when there is also
an electrical interlocking system
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automatic, by adding an automatic
controller that manages switching
from one source to another
according to a number of external
parameters.
S1
S2
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