ABB Endura APA592 Operating Instruction page 59

Endura APA592
pH / Redox (ORP) transmitter
Calibrate Parameters
Parameter
Temperature Cal
Edit PV, Temp Cal
PV Slope
PV Offset
Temp Slope
Temp Offset
Reset PV, Temp Cal
Analog Output Trim
OI/APA592–EN Rev. E
Description
The temperature calibration is used to calibrate the temperature input from
the sensor against a standard known reading – see Table 7.5, page 62.
A two-point temperature calibration is performed using this routine by
calibrating, in succession, at a low temperature value and a high temperature
value (the two values separated by at least 20 °C [68 °F]).
This results in both temperature slope and offset computation.
Note – ORP. The temperature effect on ORP sensors is negligible. The effect
of temperature on pION sensors is difficult to characterize, except for specific
applications. Therefore, only the solution coefficient option can be used to
compensate for electrode and process changes with temperature.
Enables manual adjustment of the sensor PV slope and offset and sensor
temperature slope and offset.
Note. This function may not be suitable for many applications, but it provides
quick, easy access to these calibration values for troubleshooting.
Edits the PV Slope value as a percentage.
Edits the PV Offset value.
Edits the Temp Slope value as a percentage.
Edits the Temp Slope value.
Resets all process sensor and temperature sensor calibration data to default
factory settings.
Adjusts the maximum / minimum output signals (4 to 20 mA, ±0.5 mA) to
maintain precise transmission of the process variable to the final monitoring
system.
The transmitter's output current is factory calibrated, however, the output can
be trimmed if required.
Note. Enabled when HART Poll Addr = 0 – see page 69.
Not applicable to HART multidrop mode where current output is not used.
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