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.
P050
Type of Reference for REF Input
3: 0-10V
P051
Value of REF Input producing Min. Reference
0.0V
P051a
Percentage of Ref_Min producing Min. Reference
100.0%
P052
Value of REF Input producing Max. Reference
10.0V
P052a
Percentage of Ref_Max producing Max. Reference
100.0%
P055
Type of Signal over AIN1 input
3: 0-10V
P056
Value of AIN1 Input producing Min. Reference
0.0V
P056a
Percentage of Ref_Min producing Min. Reference
100.0%
P057
Value of AIN1 input producing Max. Reference
10.0V
P057a
Percentage of Ref_Max producing Max. Reference
100.0%
C028
Min. Motor Speed
0rpm
C029
Max. Motor Speed
1500rpm
C143
Selection of Reference 1
1: REF
C144
Selection of Reference 2
2: AIN1
C179
MDI for Source Selection
0: Disable
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):
C028
Min. Motor Speed
50rpm
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:
P051a
Percentage of Ref_Min producing Min. Reference
50.0%
P056a
Percentage of Ref_Min producing Min. Reference
50.0%
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:
P052a
Percentage of Ref_Max producing Max. Reference
50.0%
P057a
Percentage of Ref_Max producing Max. Reference
50.0%
In that way, each reference will range from 25 to 750rpm and their sum will range from 50 and 1500rpm, as required.
