
11
pH 4.00
1. Clean the pH probe in distilled water.
2. Place the probe in the pH 4 calibrating fluid.
3. Press the Prog/Enter button and Cal 4 button simultaneously – the display is flashing and is
set to pH 4.00.
4. After 30 seconds, the calibration is completed and the indicator stops flashing. The pH-value of
the calibration fluid is shown.
Note: Pay attention to the temperature. If necessary, measure the temperature of the calibration
fluid.
For continuous measurement, the pH-probe must be securely placed 5 cm below the surface of the
water and the shaft has to be kept dry (we recommend the A ua Medic electrode holder).
The unit is now ready for use. As soon as the pH-value exceeds the desired adjusted value, the unit
activates the power plug.
9. Probe
The A ua Medic probe is specifically designed to determine the pH-value in fluid based solubles. It
can be used in the chemical industry, medical areas and in research laboratories.
9.1. Tec nical Data
Measurement range: pH 0 - 14
Sample temperature: 5 - 60°C, short-term
Connection: BNC-plug
Material: Plastic shaft, Polysulfon
9.2. Measurement/Maintenance
- The tip of the probe must continuously be submerged in the solution while measuring.
- A new probe or one which has been dry for a longer period must lay in water for at least 24
hours.
10. Malfunctions
- The unit indicates incorrect values --> calibrate the probe.
- The probe cannot be calibrated:
--> check glass probe for damage
--> check the content of electrolytes on the refillable probe
--> replace the probe (average probe lifespan is 1 - 3 years).
11. Set up of a complete pH-control system at t e aquarium
With the pH-computer, a complete pH-control can be realized at the a uarium. For this, you need
in addition to the pH-computer an A ua Medic solenoid valve and CO
2
complet. This contains the
steel bottle for CO
2
, the pressure regulator regular, the bubble counter and the CO
2
reactor to get
CO
2
into the a uarium
.
The CO
2
unit is mounted following the instructions. Between the CO
2
bottle and the bubble counter,
the solenoid valve is mounted close to the pressure regulator. The solenoid valve is inserted into
the connection plug of the pH-computer. The computer is programmed and calibrated, following
the instructions. The pH-probe is fixed in the a uarium at a dark and good circulated place. As
soon as the pH in the a uarium raises above the adjusted set point, the computer opens the
solenoid valve and CO
2
is injected into the a uarium via the CO
2
reactor.
If the adjusted set point is reached, the solenoid valve closes and the CO
2
addition stops. The
adjustment of the needle valve at the pressure regulator should not be at a too high bubble count.
It should be adjusted in a way that even if the solenoid valve fails (e .g. due to clogging by dirt)
the pH-value in the a uarium does not decrease to critical values.