18 Conductivity indicator
54
“Unlocking the levels”, page 27, (code word 0110)
✱
Immerse the sensitive portions of the cell and the temperature probe or
thermometer in the calibration solution
– wait until the temperature and conductivity measurements have
stabilized.
✱
Press the
and
keys – “CAL.1” appears in the lower display,
alternating with the measured or manually set temperature.
✱
Use the
and
keys to set the indicated conductivity to the real
conductivity of the calibration solution at the temperature now prevailing.
✱
Press the
key (saves the new cell constant and returns to the
measurement mode).
18.7.2 Automatic determination of the relative cell constant with a
reference instrument
If the deviation of the cell constant from its nominal value is not known, then it
can be automatically determined.
You will need
A conductivity measuring instrument to serve as a reference.
Initial condition
The conductivity transmitter is connected to the JUMO dTRANS Az 01
Chapter 18.1 “Conductivity measurement circuit”, page 48ff.
The calibration procedure has been configured to “Calibration of the cell
constant, process value output ...” – frozen or not frozen,
Chapter 26.4 “Controller options - C211”, page 76.
The instrument is in the measurement mode,
“Operating modes and states”, page 24.
Procedure
✱
Unlock the instrument for calibration,
“Unlocking the levels”, page 27, (code word 0110)
✱
Immerse the sensitive portions of both cells in the calibration solution
– wait until the measurements for both instruments have stabilized.
✱
Press the
and
keys on the instrument – “CAL.1” appears in the
lower display, alternating with the measured or manually input temperature.
✱
Use the
and
keys to set the indicated conductivity to match the
value shown on the reference instrument.
✱
Press the
key (saves the new cell constant and returns to the
measurement mode).
PGM
PGM
The temperature coefficient of the reference instrument must be set
to “0” ! If this is not possible, then the solution being measured must
be tempered to the reference temperature for the reference
instrument.
PGM
PGM
