ABB Advant Controller 450 User Manual

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First analyze the application to determine where you can take the most effective optimization
action. Primarily, you can take optimization action in three areas, I/O, PC and communication.
As usual with optimization, it is most profitable to optimize the part which uses the most CPU-
power.
Recommendations for optimization in these three areas are given below.
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• If many interrupt-controlled DIs with high frequency of change are used, it can be optimal
to go over to cyclically scanned DI, if this is permissible from the time-tagging viewpoint.
The form for “Calculations of CPU-load from inputs” can indicate if this is optimal with
interrupt-controlled or scanned DI.
• Are I/O signals scanned with an unnecessarily short cycle time? I/O signals normally need
not be scanned more often than the cycle time of the execution unit in the PC in which they
are used. Note that it may be necessary to scan AI quickly because of the frequency
content of the input signal. The signal can be low pass-filtered in AI software,
thus providing frequency components with lower frequency in the signal which the
application program uses. This means that the application program can be run more slowly
than the corresponding AI is scanned.
• Select as large dead-band for the AI channel as possible. Of course the accuracy
requirement must be considered.
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• Check that no execution unit is executed with an unnecessarily short cycle time.
• If possible, break out parts of an execution unit or execution units and allocate to these a
longer cycle time.
• Utilize the option to block execution units when they need not be executed. It is also
possible to introduce a BLOCK element here when only parts of an execution unit can be
blocked.
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• You can transmit Data Sets event-controlled on a MasterBus 300 with the help of the PC
element SENDREQ. Use the VALID flag in the receiving DS as an acknowledgment that
the signal is received.
• Always present digital signals on the operator station screen with event-controlled update
in combination with 9 sec cyclic update, to get fast updating on changes while minimizing
the load.

ABB Advant Controller 450 Specifications

General

Brand	ABB
Model	Advant Controller 450
Category	Controller
Language	English