Hach Ultra ORBISPHERE 3658, Руководство оператора для быстрого использования

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BAROMETRIC PRESSURE SENSOR
The instrument internal barometric pressure
sensor is calibrated at the factory, and normally
requires no further attention. However, you may
w i s h t o c a l i b r a t e i t a g a i n s t y o u r o w n
instrumentation, or simply check the instrument
for accuracy.
Select
Troubleshooting , Pressure Calibration
from the Hach Ultra 3658 program, and enter the
current atmospheric pressure, in mbars, in the
calibration pressure entry box.
GAS SENSOR
The sensor can be calibrated in a liquid solution
w i t h a k n o w n c o n c e n t r a t i o n o f C O
2
( w e
recommend using the ORBISPHERE High
Precision Calibration Kit), or in pure CO
2
gas at
atmospheric or elevated pressure.
Before calibrating check that the sensor
membrane surface is tight, smooth and wrinkle
free. Select the calibration medium using the
Hach Ultra 3658 program.
Ensure that normal measurement mode is
selected in the Measurement Mode menu of the
Hach Ultra 3658 program
Calibration must only be carried out once the TC
sensor is giving a stable measurement. Expose
the membrane to the calibration sample until this
stable reading is obtained. This usually takes
about 5 minutes.
For calibration it is important that the sensor's
membrane is at the same temperature as the
calibration sample. Therefore, allow some sample
to pass through the flow chamber for 3 minutes
before calibrating.
If calibrating in gas, ensure that the flow chamber
and sensor components are completely dry.
Remove and blow dry the flow chamber, and dry
the sensor head surface with a clean soft tissue.
Ensure that the purge cycle is running correctly by
placing the purge gas exit tubing into water. This
rate should be more than four bubbles during the
purge which lasts for 4 seconds. This purge cycle
is repeated every 20 seconds.
Note :
When press the CAL button, remember that this
button may have been locked out by the Hach
Ultra 3658 program to prevent an accidental
reset.
In all calibration methods, calibration is successful
or in error, as per the following definitions:
• If the instrument makes two consecutive
measurements with less than 1%
difference, it calibrates against this
stabilized value. The LCD then displays
the message
[CAL]
to indicate
calibration has been successfully
completed
• If the calibration does not complete, the
LCD displays the message
[Err]
. The
reason for this calibration error is either
that the measured gas partial pressure is
under 5 mbar, or that a wrong instrument
key was pressed during the calibration
steps.
Calibration in a Liquid Solution
The sensor can be calibrated in a liquid solution
that has a known concentration of CO
2
.
Calibration