Aqua Medic pH computer Manual De Instrucciones página 7

5. Adjustment of the control direction
The status of the control direction is shown at the LED's at the side:
High: An adjusted maximum set point is controlled by adding some reducing agent. The control direction is
downwards. This is the standard mode for controlling the pH in fresh water or salt water aquaria by
adding CO .
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Low: An adjusted minimum set point is controlled by adding some oxydizing agent (e. g. ozone). The control
direction is upwards.
To change the control mode between High and Low, press Prog./Enter and the High/Low button
simultaneously. The actual mode is shown by the LED's (4).
6. Adjusting the set point
To adjust the set point, press Prog./Enter and the SET buttons simultaneously. The adjusted set point is now
shown on the display – flashing. It can be changed with the + and – buttons. By pressing the Prog./Enter
button again, the set-point is saved and the display switches back to the actual value.
7. Adjusting the hysteresis
The hysteresis is the range between switching on and off. If the set point is adjusted to pH 7.00 and the
hysteresis is set to 0.05 pH, the unit switches on if the set point of pH 7.00 is reached and after reaching 6.95,
it switches off again. We do not recommend to adjust the hysteresis to very low values, e. g. 0.01 pH, because
this will result in too frequent switching. A good value for the hysteresis is 0.05 pH.
To adjust the hysteresis, press the Prog./Enter and the Hys buttons simultaneously. The adjusted hysteresis
is now shown on the display – flashing. It can be changed with the + and – buttons. By pressing the Prog./Enter
button again, the value is saved and the display switches back to the actual value.
8. Sensor calibration
Calibration:
The standard pH 7 and pH 4 calibrating fluids are used to calibrate the pH probe.
pH 7
Clean the pH probe in distilled water and place the probe in the pH 7 calibrating fluid. Press the Prog./Enter
button and Cal 7 button simultaneously – the display is flashing and is set to pH 7. 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. It should
correspond to the aquarium's water temperature.
pH 4
Clean the pH probe in distilled water and place the probe in the pH 4 calibrating fluid. Press the Prog./Enter
button and Cal 4 button simultaneously – the display is flashing and is set to pH 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. It should
correspond to the aquarium's water temperature.
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 Aqua 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 Aqua 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.
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