PROGRAMMING GUIDE
SINUS PENTA
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36.2. How to Manage the Reference Sources
This section covers how to manage the reference sources.
Two examples are given along with the table including the configuration of the parameters to be used.
Example 1: The Speed Reference is the algebraic sum of two references
Analog inputs REF and AIN1 (that are supposed to be 0-10V voltage inputs) are to be used as speed references. The
main reference will be the sum of the two references being used. The end result may vary based on the parameters
concerned.
Type of Reference for REF Input
Value of REF Input producing Min. Reference
Percentage of Ref_Min producing Min. Reference
Value of REF Input producing Max. Reference
Percentage of Ref_Max producing Max. Reference
Type of Signal over AIN1 input
Value of AIN1 Input producing Min. Reference
Percentage of Ref_Min producing Min. Reference
Value of AIN1 input producing Max. Reference
Percentage of Ref_Max producing Max. Reference
C179=0: Disable ensures that the main reference is the sum of the references being used. If a digital input for Source
selection were used, either one reference would be selected as the main reference based on the input status.
Both REF and AIN1 references are programmed in order to meet the following requirements:
• at 0V, they are expected to generate 100% of the minimum motor speed reference (C028), i.e. 0rpm
• at 10V, they are expected to generate 100% of the maximum motor speed reference (C029), i.e. 1500rpm
The main reference will be their sum and will start from 0rpm (when both references are at 0V) and its maximum value
would be 3000rpm (when both references are at 10V), but it will be limited to 1500, as set by C029, as soon as the sum
of the two references exceeds 1500rpm.
Suppose that the parameters below are to be programmed (only the parameters changing with respect to the example
above are given):
As the minimum motor speed is set to 50rpm, each of the two references, at 0V, will generate a reference equating
100% of 50rpm, i.e. 50rpm. The minimum value of the main reference, that is the sum of the two references, will then
equating 100rpm if the two references are at 0V.
If the main reference shall start from 50rpm, that is it can generate the minimum motor speed, the following parameters
shall be set accordingly:
Percentage of Ref_Min producing Min. Reference
Percentage of Ref_Min producing Min. Reference
In that way, either references at 0V will generate 50% of 50rpm, i.e. 25rpm. Their sum will be worth 50rpm at a
minimum, as required.
If the whole resolution of the references is to be exploited, so that:
• at 0V, for both references, the minimum speed is 50rpm
• at 10V, for both references, the maximum speed is 1500rpm
then the following shall be programmed:
Percentage of Ref_Max producing Max. Reference
Percentage of Ref_Max producing Max. Reference
In that way, each reference will range from 25 to 750rpm and their sum will range from 50 and 1500rpm, as required.