horiba U-51, Инструкция по эксплуатации

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3 Basic Operation
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3.3 Calibration
To obtain correct measurement values, the sensors need to be calibrated using standard
solution before measurement. You can select simultaneous auto calibration of the pH, COND
and TURB sensors in pH4 standard solution and DO and DEP sensors simultaneously in air,
or manual calibration of individual measurement parameters. You can check the result of the
previous calibration using the procedure on “ 3.5.4 Checking the calibration record ” (page
72).
Note

Wait at least 30 minutes after turning the system power ON before calibrating the DO sensor.

Make the DO and COND compensation settings before calibration since these settings are
applied during calibration.

You can select only the desired parameters for calibration and calibrate just those parameters
(see “ 3.2.4 Sensor selection ” (page 25)).

Use about 200 mL of standard solution in the calibration cup.

Calibration data is stored in the sensor probe.
3.3.1 Auto calibration
Tip

The following parameters are calibrated (at 25

C):
pH: Set to 4.01 (zero-point calibration); the span is adjusted to the factory default value.
COND: 0.449 S/m (4.49 mS/cm, span calibration); the zero point is adjusted to the factory default
value.
TURB: 0 NTU (zero-point calibration); the span is adjusted to the factory default value.
DO: 8.92 mg/L (span calibration); the zero point is adjusted to the factory default value.
DEP: 0 m (zero-point calibration); the zero point is adjusted to the factory default value.

If the air temperature changes, the readout value may not be stable. Ensure that the ambient air
temperature is the same temperature as the calibration solution, because the internal probe
temperature sensor and external temperature sensor (in the calibration solution) are used for the
auto calibration. Allow the probe and standard solution to equilibrate for 1 hour if a thermometer
is not available to verify that these temperatures are the same.

Do not hold the probe while performing the auto calibration. Body temperature may elevate the
internal temperature sensor measurement creating DO calibration error.
1. Remove the sensor guard and wash the sensor probe 2 or 3 times with deionized
water.
sensor guard