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6 Calibration
6.1
Notes
6.2
General
JUMO tecLine CR-4P conductivity sensors are exactly gaged at the factory.
The cell constant of every measuring sensor is documented both on the cell
stem and on the calibration certificate that is also supplied.
This cell constant should be entered directly into the connected transmitter
(e. g. JUMO AQUIS 500 CR).
In combination with the JUMO AQUIS 500 CR, measuring accuracy in the
20 µS/cm to 600 mS/cm range is better than 5 %. To achieve far greater
measuring accuracy, calibrate the transmitter close to its later working point.
To monitor and increase the quality of measurement, the conductivity
measurement chain (conductivity connecting cable + transmitter)
should be regularly calibrated.
Reference solutions
It is advisable to use one of the following reference solutions for calibration:
• ASTM D 1125, reference solution B: 0.1 N KCl with 12856 µS/cm
• DIN 38404, Part 8, Section 8.3: 0.1 mol/l KCl with 12.95x10
3
µS/cm
However, any calibration solution in the medium conductivity range can also
be used.
6.3
JUMO AQUIS 500 CR settings
The following settings are the minimum that have to be made:
• Cell type (type of connection): 4-electrode or 4-wire
• Nominal cell constant 1.0 1/cm
• Relative cell constant as % (see sensor nameplate or
certificate)Einstellungen am JUMO dTRANS CR 02
Ageing and contamination (deposits) can cause the cell constant
of the conductivity sensor to change.
The transmitter should therefore be calibrated to the connected
conductivity sensor at regular intervals (subject to the measuring
material and the operating conditions)!
It is essential to comply with the JUMO AQUIS 500 CR operating
instructions (B 202565.0)!