ACH550-UH User’s Manual
209
Serial Communication – FBA
and
REF
2). Note, fieldbus references are bipolar, that is they can be positive or
negative.
Actual Value
As described earlier in "Control Interface", Actual Values are words containing drive
values.
Actual Value Scaling
The scaling of the integers sent to the fieldbus as Actual Values depends on the
resolution of the selected drive parameter. Except as noted for Data Words 5 and 6
below, scale the feedback integer using the resolution listed for the parameter in the
"Parameter Descriptions" section. For example:
ABB Drives Profile
Parameter
Value Setting
AI Reference Scaling
1003
DIRECTION
1 (
FORWARD
)
1003
DIRECTION
2 (
REVERSE
)
1003
DIRECTION
3 (
REQUEST
)
Feedback Integer
Parameter Resolution
Scaled Value
1
0.1 mA
1 * 0.1 mA = 0.1 mA
10
0.1%
10 * 0.1% = 1%
100%
Max. Ref
-100%
-163%
163%
-(Max. Ref.)
Fieldbus
Resultant Ref.
Reference
100%
Max. Ref
-100%
-163%
163%
-(Max. Ref.)
Fieldbus
Resultant Ref.
Reference
100%
Max. Ref
-100%
-163%
163%
-(Max. Ref.)
Fieldbus
Resultant Ref.
Reference