Hach-Lange POLYMETRON 9526 - Manual (Page 17)

Calibration
About sensor calibration
There are no calibration options available from the menus of the 9526 instrument. All calibrations are
performed from the controller of the sensor under test. For detailed information on these calibration
procedures refer to the associated manuals delivered with the sensor and controller under test.
N O T I C E
After turning on the 9526 instrument and initiating sample circulation, wait for at least 30 minutes in order to allow
correct rinsing of the whole system. This also enables the temperature equilibration between the sample, the flow
chamber and the sensor.
After 30 minutes of sample circulation, compare the measurement value displayed on the controller
under test against the measurement value displayed on the 9526 instrument. If these values are
outside ± 5% of each other than a calibration is required. If these values are within ± 5% of each
other than a calibration is not necessary but can still be performed.
Before calibrating the sensor under test, make sure to perform a temperature calibration first.
Calibration process
All calibrations are made using the controller and sensor under test. Follow the instructions in the
associated controller and sensor user manuals.
The process can be different according to the Polymetron controller under test. Perform the
calibration process in the following sequence.
1. Temperature calibration
The following equipment is required for a temperature calibration:
• Pt100 simulator (< 0.1 °C) for a 2-point electrical calibration
• Certified precision thermometer (< 0.1 °C) if connected in-line
• None if mounted off-line as the 9526 is used as the reference
Polymetron controller model under test
9500 9125 Others
2-point electrical
calibration NO YES (100 and 172 Ω) NO
Process calibration YES YES YES
2. Electrical calibration
Polymetron controller model under test
9500 / 9125 9125 (< V1.12) / 8925 / Others 8920
R∞ 1 and 200 kΩ 2 NO R∞ 1
1 Cable disconnected from the sensor or sensor exposed to air
2 Use the precision resistance on the 9526
3. Conductivity calibration
Polymetron controller model under test
9500 / 9125 / 8920 9125 (< V1.12) / 8925 Others
K calculation (see K Calculation
on page 18). On the controller
under test, enter the K Cell value
computed by the Polymetron 9526
Process: R∞ and comparative
measurement with 9526 1
Process: Comparative
measurement with 9526 1
1 Adjust the displayed value of the transmitter under test to that of the 9526 value
English 17