National Instruments FP-3000 - Manual (Page 90)

Appendix B Fieldbus Parameters
FieldPoint FP-3000 User Manual B-12 www.ni.com
ITK_VER
The version of the Interoperability Test Kit with which this device was
tested.
L_TYPE (Scaling)
The linearization type. This parameter affects the way the value from the
transducer is linearized in the analog input block before it is presented as
the block output. In all cases, the
FIELD_VAL parameter behaves as
follows:
FIELD_VAL = 100 * (transducer_value – XD_SCALE.EU0) /
(XD_SCALE.EU100 – XD_SCALE.EU0)
FIELD_VAL can be simply described as the percentage of span reading
from the transducer, and therefore its units are percent.
Use PV for BKCAL_OUT When set, uses the process variable as the value for
BKCAL_OUT , instead of the setpoint.
Low Cutoff When set, enables the AI low cutoff parameter.
Table B-6. Linearization Types
Type Description
Direct The block output is directly taken from the transducer value:
OUT = transducer_value
Indirect The block output is scaled according to OUT_SCALE from the value
in FIELD_VAL :
OUT = OUT_SCALE.EU0 + ((FIELD_VAL/100) *
(OUT_SCALE.EU100 – OUT_SCALE.EU0))
Indirect Square Root The block output is scaled according to OUT_SCALE from the value
in FIELD_VAL . Before the field value is rescaled, the square root is
taken.
OUT = OUT_SCALE.EU0 + (SQRT(FIELD_VAL / 100) *
(OUT_SCALE.EU100 – OUT_SCALE.EU0))
Uninitialized An invalid setting. The device reports a configuration error with an
Uninitalized
L_TYPE .
Table B-5. Operation Bitmasks (Continued)
Bitmask Description