Calculation of process data

The terminal records measured values continuously and places the raw value of its A/D converter into the ADC raw value object 0x80nE:01. The calculation of the correction with the vendor calibration values takes place after each acquisition of the analog signal. This is followed by (optional) user calibration, user scaling and evaluation of the limits (see diagram Calculation of process data)

Calculation of process data 1:
Calculation of process data

Calculation

Designation

XADC

Output of the A/D converter

YH = (XADC - BK) x AK x 2-14
YH = (XADC - 0) x 214 x 2-14
YH = XADC

Measured value after vendor calibration (corresponds to the raw value of the A/D converter)

YAK = (YH - BAK) x AAK x 2-14
YAK = (XADC - BAK) x 214 x 2-14
YAK = XADC, if index 0x80n0:0A (enable user calibration)

Measured value after vendor and user calibration

YA = YAK x AW x 2-16 + BW
YA = YAK , if index 0x80n0:01 (enable user scale) inactive
YA = XADC , if index 0x80n0:01 and index 0x80n0:0A inactive

Measured value following user scaling

Legend

Name

Designation

Index

XADC

Output value of the A/D converter

0x80nE:01

BK

Vendor calibration offset (cannot be changed)

0x80nF:01

AK

Vendor calibration gain (cannot be changed)

0x80nF:02

BAK

User calibration offset (can be activated via index 0x80n0:0A)

0x80n0:17

AAK

User calibration gain (can be activated via index 0x80n0:0A)

0x80n:018

BW

User scaling offset (can be activated via index 0x80n0:01)

0x80n0:11

AW

User scaling gain (can be activated via index 0x80n0:01)

0x80n0:12

YA

Process data for controller

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