ABB ACS355 series - Fieldbus References

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 – 1103 REF1 SELECT or 1106 REF2 SELECT – to
COMM, COMM+AI1 or COMM*AI1. When parameter 1103 or 1106 is set to COMM,
the fieldbus reference is forwarded as such without correction. When parameter 1103
or 1106 is set to COMM+AI1 or COMM*AI1, the fieldbus reference is corrected using
analog input AI1 as shown in the following examples for the ABB drives profile.
Setting When COMM > 0 When COMM < 0
COM
M+AI1
COMM(%)
· (MAX-MIN) + MIN
+ (AI(%) - 50%)
· (MAX-MIN)
COMM(%)
· (MAX-MIN) - MIN
+ (AI(%) - 50%)
· (MAX-MIN)
Maximum limit is defined by parameter 1105 REF1 MAX / 1108 REF2 MA.
Minimum limit is defined by parameter 1104 REF1 MIN / 1107 REF2 MIN.
AI = 50%
AI = 100%
AI = 0%
1500
Corrected
reference (rpm)
750
0
Max. limit
Min. limit
COMM
REF (%)
100500
AI = 50%
AI = 0%
AI = 100%
COMM
REF (%)
Corrected
reference (rpm)
0
-750
-1500
-100 -50 0
Max. limit
Min. limit
AI = 50%
AI = 100%
AI = 0%
Corrected
reference (rpm)
Max limit
Min limit
COMM
REF (%)
100500
1500
750
0
1200
300
AI = 50%
AI = 0%
AI = 100%
COMM
REF (%)
0
-750
-1500
-100 -50 0
-300
-1200
Corrected
reference (rpm)
Max. limit
Min. limit