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Connect the probe to the instrument and switch on with button
; the device turns on and starts the
countdown for the polarization time. At the end of the countdown, the meter enters in measure mode
and it is ready to perform measurements.
The polarization time is 10 minutes.
However, if the instrument is turned off for less than an hour, the
polarization time will reduce proportionally.
•
New sensor with new instrument
The sensor is supplied with the membrane filled with electrolyte; it is necessary to hydrate the membrane
dipping it in distilled water for half an hour. Switch the device on and wait for the polarization time.
•
Probe storage
When the probe is not in use, store it in the storage cap containing distilled water. In this way, the
membrane is protected and hydrated, ready for use.
•
Not using the sensor for long period of time: over one month
If the instrument and the sensor are not used for a long period of time (over one month), it is recommended
to empty the membrane from the electrolyte and wash the probe accurately. Dry the sensor and screw the
membrane without electrolyte, protecting the sensor with its rubber cap.
•
Oxygen sensor calibration
The polarographic sensor is an active sensor which changes its response with wear and aging; therefore,
it is necessary to perform the calibration regularly in air.
•
Calibration in air at 100%
The ordinary calibration is performed at 100% in air.
Turn the instrument on, dip the probe in water and wait for the polarization time of 10 minutes.
Later, dry the probe thoroughly with paper towel and proceed as follows:
•
Place the probe in air with the membrane facing downwards and wait for 2 minutes. Then, connect the
sensor to the device.
•
In measure mode, press the key
to enter in calibration mode.
On the display, it appears the string “
POINT oxy 100.0
”; the device will look for the value %O
2
= 100 %.
Keep the sensor in air in a vertical position with the membrane facing downwards.
•
When the signal is stable, the red bands will be replaced by the stability icon
.
Press the button
, as indicated by the string “
PRESS OK
”.
On the display, the measured value flashes, then the sensor and finally the beacker
appears
below on the left and indicates that the instrument is calibrated on value 100%O
2
.
•
After the calibration, the instrument enters in measure mode automatically.