Fieldbus References; Reference Selection And Correction - ABB ACS355 User Manual

332 Fieldbus control with fieldbus adapter

Fieldbus references

Reference selection and correction

Fieldbus reference (called COMM in signal selection contexts) is selected by setting a
reference selection parameter –
COMM, COMM+AI1
the fieldbus reference is forwarded as such without correction. When parameter
or 1106 is set to COMM+AI1
analog input AI1 as shown in the following examples for the DCU profile.
With the DCU profile the fieldbus reference type can be Hz, rpm or percent. In the
following examples the reference is in rpm.
Setting When COMM > 0 rpm
COMM COMM/1000 + (AI(%) - 50%) · (MAX-MIN) COMM/1000 + (AI(%) - 50%) · (MAX-MIN)
+AI1
Corrected
reference (rpm)
1500
AI = 100%
750
AI = 50%
0
0
Corrected
reference (rpm)
1500
1200
AI = 100%
750
AI = 50%
300
0
0
Maximum limit is defined by parameter
Minimum limit is defined by parameter
1103 REF1 SELECT
or COMM*AI1. When parameter
or COMM*AI1, the fieldbus reference is corrected using
Max. limit
AI = 0%
Min. limit
750000 1500000
COMM
REF
Max limit
AI = 0%
Min limit
COMM
REF
750000 1500000
or 1106 REF2 SELECT
1103 or
When COMM < 0 rpm
COMM
-1500000
REF
Min. limit
Max. limit
COMM
-1500000
REF
Min. limit
Max. limit
1105 REF1 MAX / 1108 REF2
1104 REF1 MIN / 1107 REF2
– to
1106 is set to COMM,
1103
-750000 0
0
AI = 100%
-7500
AI = 50%
AI = 0%
-1500
Corrected
reference (rpm)
-750000 0
0
-300
AI = 100%
-750
AI = 50%
AI = 0%
-1200
-1500
Corrected
reference (rpm)
MAX.
MIN.