Fieldbus References - ABB ACS355 series User Manual

320 Fieldbus control with embedded fieldbus

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 ABB drives profile.
Setting
COM COMM(%) · (MAX-MIN) + MIN
M+AI1 + (AI(%) - 50%) · (MAX-MIN)
Corrected
reference (rpm)
1500
AI = 100%
750
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
When COMM > 0
Max. limit
AI = 50%
AI = 0%
Min. limit
50 100
COMM
REF (%)
Max limit
AI = 0%
Min limit
COMM
REF (%)
50 100
or 1106 REF2 SELECT
1103 or
When COMM < 0
COMM(%) · (MAX-MIN) - MIN
+ (AI(%) - 50%) · (MAX-MIN)
COMM
-100
REF (%)
Min. limit
Max. limit
COMM
-100
REF (%)
Min. limit
Max. limit
1105 REF1 MAX / 1108 REF2
1104 REF1 MIN / 1107 REF2
– to
1106 is set to COMM,
1103
-50 0
0
AI = 100%
-750
AI = 50%
AI = 0%
-1500
Corrected
reference (rpm)
-50 0
0
-300
AI = 100%
-750
AI = 50%
AI = 0%
-1200
-1500
Corrected
reference (rpm)
MA.
MIN.