Zero Compensation / Calibration

The terminal has an optional self-calibration function for offset compensation in the event of significant temperature drift or large voltage jumps. If necessary, it can be used to further reduce the specified measurement uncertainty in individual cases.

Fig.144: CoE Index 0x8000:19, Zero Compensation Interval

It is set via Zero Compensation Interval (CoE Index 0x8000:19) and works accordingly

• "Off": not at all (default setting)
• repeated after a corresponding time interval
• "Triggered by PDO": by manually triggering via PDO (rising edge)

Fig.145: Process data "Start calibration"

The compensation function compensates the internal offset drift of the ADC. For approx. 400 ms

• the input will be short-circuited internally and the offset will be measured
• the value is displayed in the CoE

Fig.146: Process data "Zero value"

• the measured value is frozen during "calibration"
• pDO Status.Calibration in progress = TRUE

Fig.147: Status "Calibration in progress"

Zero Compensation Interval and Frequency = 50 Hz In the 50 Hz setting (0x8000:0A), it is recommended not to use the function (0: Off)!