Robo-Tank DIY All-In-One Aquarium Controller User Manual
Robo-Tank DIY All-In-One Aquarium Controller
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User Manual v4.05 – Page 50
Calibrating a pH Probe – PH1 & PH2
Atlas EZO PH circuits can be calibrated several ways:
1 (Mid) Point Calibration
2 (Mid & Low)Point Calibration
3 (Mid, Low & High) Point Calibration
A pH (potential of Hydrogen) probe measures the hydrogen ion activity in a liquid.
Calibrating a pH probe, requires the use of one or more pH calibration buffer solutions. Currently you can use the following
calibration solutions:
pH 4.0 or 4.1
pH 7.0 or 7.1
pH 10.0 or 10.1.
These solutions are available from various sources, for example; pH 4.0/7.0/10.0 buffer solutions can be obtained from
Atlas-Scientific, and pH 4.1/7.1/10.1 buffer solutions from Milwaukee Instruments, or any reputable supplier.
You can calibrate with one solution, (the mid-point pH 7.x), but the accuracy of the reading improves with the use of each
additional solution (Low point & High point). Simply select which solution you’re using on the screen above, (below the pH
icons).
Select pH1 or PH2, in this case pH 1 was selected, it
takes you to the screen at left, CALIBRATE PH.
Select the calibration method, in this case we
select 1 Point Calibration.
*NOTE: The Atlas pH circuit is set to a default temperature compensation of 25
o
C. Temperature variations of < 2
o
C are
insignificant.
As an example, having selected 1 Point Calibration,
you’ll see the screen to the left.
For this calibration you will need a PH 7.0 solution,
corresponding to the value you selected on the
CALIBRATE ATLAS PROBE screen, and which
appears here as the Target pH.
Pour enough calibration solution into a clean glass,
beaker or jar (rinse out with RO or distilled water),
to cover the end of the probe, swirl the probe
about to ensure full contact with the solution and
to dislodge any trapped air.
At the top of the screen, it confirms how many points the calibration this is, in this case a Single Point Calibration, and
which step you’re currently on.
