Atlas Scientific EZO-pH, Руководство пользователя

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Calibration theory
The Atlas Scientific EZO
™
class pH circuit has a flexible calibration protocol, allowing for
single point, two point,
or
three point
calibration.
The EZO
™
pH circuits default temperature compensation is set to 25° C. If the temperature
of the calibration solution is +/- 2° C from 25° C, consider setting the temperature
compensation first.
Temperature changes of < 2° C are insignificant.
The first calibration point must be the Midpoint (pH 7)
Single point calibration
1. Remove soaker bottle and rinse off pH probe.
2. Pour a small amount of the calibration solution into a cup.
3. Let the probe sit in calibration solution until readings stabilize
(1 – 2 minutes).
4. Calibrate the midpoint value using the command "Cal,mid,n" .
Where "n" is any floating point value that represents the calibration midpoint.
5. Do not pour the calibration solution back into the bottle.
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“Cal,mid,n”
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“Cal,low,n”
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“Cal,high,n”
Lowpoint Highpoint Midpoint
14
"cal,low,n" "cal,mid,n" "cal,high,n"
The most important part of calibration is watching the readings during the calibration
process. It's easiest to calibrate the device in its default state (UART mode, continuous
readings). Switching the device to I
2
C mode after calibration will not affect the stored
calibration. If the device must be calibrated in I
2
C mode be sure to request readings
continuously so you can see the output from the probe.
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