ABB ACS550 - Actual Value Mapping

ACS550 User’s Manual 241
Fieldbus adapter
Actual Value scaling
For Actual Values, scale the feedback integer using the parameter’s resolution. (See
section Complete parameter list on page 85 for parameter resolutions.) For example:
Where parameters are in percent, the Complete parameter list section specifies
what parameter corresponds to 100%. In such cases, to convert from percent to
engineering units, multiply by the value of the parameter that defines 100% and
divide by 100%. For example:
Actual Value mapping
See the user’s manual supplied with the FBA module.
Feedback
integer
Parameter resolution
(Feedback integer) · (Parameter resolution) =
Scaled Value
1 0.1 mA 1 · 0.1 mA = 0.1 mA
10 0.1% 10 · 0.1% = 1%
Feedback
integer
Parameter
resolution
Value of the
parameter that
defines 100%
(Feedback integer) · (Parameter resolution) ·
(Value of 100% ref.) / 100% =
Scaled Value
10 0.1% 1500 rpm
1
10 · 0.1% · 1500 RPM / 100% = 15 rpm
100 0.1% 500 Hz
2
100 · 0.1% · 500 Hz / 100% = 50 Hz
1
Assuming, for the sake of this example, that the Actual Value uses parameter 9908 MOT NOM SPEED
as the 100% reference and that 9908 = 1500 rpm.
2
Assuming, for the sake of this example, that the Actual Value uses parameter 9907 MOT NOM FREQ
as the 100% reference and that 9907 = 500 Hz.