JUMO 202550 Operating Instructions Manual page 42

14 Redox indicator
1-point
calibration
2-point
calibration
Manual
entry
Temperature
Preparation for
calibration
Calibration
with / without
"frozen process
value output"
40
calibrated, either the zero point on the instrument should be set to 0.0 mV (see
below, manual entry) or single-point calibration should be performed.
In 1-point calibration the electrode zero is freshly determined using a buffer
solution (solution with a known redox voltage).
[
The display unit mV
Chapter 17.2 "Analog inputs - C111", page 46.
In 2-point calibration, the start and end values can be freely defined (for
applications such as decontamination control).
[ ]
The display unit %
Chapter 17.2 "Analog inputs - C111", page 46.
In addition to the calibration procedure described above, the indicator/
controller offers the facility of manually entering the zero point (as determined
by a laboratory, for example),
Chapter 17.3 "nuLL - SLoP", page 47.
The measurement of the redox voltage does not take temperature into
account; neither automatic nor manual temperature compensation is required.
Cancel
You can change back to the measurement mode at any time, by
pressing the
Before the first calibration, the following has to be determined:
- the calibration procedure (1-point or 2-point calibration)
whether the process value output is frozen or not during calibration.
Chapter 26.4 "Controller options - C211", page 76.
If subsequent calibrations are carried out with the same settings,
then it will not be necessary to set them again.
"Freezing" the process value output means that, during calibration, the output
signal is held at the value that was produced immediately before calibration
started. This is to avoid an uncontrolled reaction from any PLC that may be
connected to the output of the indicator/controller.
While the process value output is frozen, the lower display shows "donE" after
the last calibration step, and the upper display shows the latest measurement.
The process value output remains unchanged!
After the electrode has been installed once more, the
again. The process value output is now coupled to the display again.
The factory setting is: "Calibration without frozen process value
output".
]
must have been selected in C111!
must have been selected in C111!
key.
EXIT
key must be pressed
PGM