Hach Ultra ORBISPHERE 3625, Руководство оператора

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68 of 90 Calibrations - 3625 Package Analyzer
Operator Manual
ORBISPHERE
After the third calibration cycle, the variation in sensitivity of the sensor is displayed as a
percentage of the last calibration.
Note:
If the 3 calibration cycles show a variation over 1%, the 3 cycles are restarted. The
instrument displays
RECAL ERR XX%
until the 3 cycles are within range.
7.6.2 Partial Pressure Calibration
Using the Orbisphere 32001.xxx calibration flow chamber, the sensor is exposed to a
known composition of CO
2
(or N
2
) between 3 and 5 bar absolute pressure (ideally close
to the partial pressure being measured), measured with an external certified pressure
gauge having a precision of ± 5 mbar.
Note:
Make sure the flow chamber is absolutely dry inside and out before use.
Procedure
•
ESC
displays main menu
• × Ø select
CALIBRATE
;
ENTER
• × Ø select
CO2
;
ENTER
• × Ø select
PARTIAL PRESSURE
;
ENTER
• × Ø select the appropriate pressure unit;
ENTER
Next, enter the pressure of the calibration gas. Enter the absolute pressure (gauge
pressure plus atmospheric pressure).
Preparation
• Disconnect the external temperature sensor cable.
• Remove the sensor from piercer.
• If sensor's head is wet, rinse the sensor tip with water,
and dry with a tissue.
• Make sure that the grille in the front of the sensor is clean
and dry.
• Insert the sensor into the calibration flow chamber.
• Connect a source of calibration gas to the flow chamber
inlet.
• Close flow chamber outlet valve to build up the requested
pressure in the system.