Decentral Solutions
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Decentralized design benefits
In the following we will concentrate on describing
decentralized installation of adjustable frequency drives
and motor starters, referred to here as motor controls.
There are two topologic concepts for the layout of motor
control installations in a plant, in the following referred
to as "centralized" and "decentralized" installations.
The two typologies are illustrated in the figure.
In a centralized installation:
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motor controls are placed in a central place
In a decentralized installation:
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motor controls are distributed throughout the plant,
mounted on or next to the motor they control
Decentralized does not mean "control cabinet free", but
merely that their enormous size can now be reduced
thanks to innovative designs of the components that
will be placed decentralized. There will continue
to be a need for cabinets for power distribution
and for overall intelligence, and there are areas,
particularly in the process industry with areas such
as explosion protection, where centralized cabinets
continue to be the preferred solution.
Centralized versus decentralized installations
Placing the advanced and reliable electronics needed
to ensure a smooth, responsive and economical
operation of the motor next to - or on - the motor
facilitates modularization and reduces cabling costs
and EMC problems dramatically. Further benefits:
•
Space-consuming motor control cabinets in long
rows of centralized panels are eliminated
•
Reduced efforts for building in and wiring long
screened motor cables where special attention
on EMC terminations is required
•
Heat dissipation from power electronics is moved
from the panel into the plant
•
Standardized machine elements by modularization
reduces design time and time to market
•
Commissioning is easier and faster
Decentralized motor control is rapidly gaining
ground despite of the advantages of the
centralized control concept:
•
no need for extra space around the motor
or close to the motor
MG.90.F2.22 - VLT is a registered Danfoss trademark
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