Dr.Thiedig Digox 6, Operating Manual

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4.2 Variables influencing calibration
4.2.1 Flow
Measurements done at open electrodes are
influenced by the flow volume. Flow volumes
between 3 and 18 litres per hour affect the
measuring value of the medium water and of the
medium beer, which is then compensated by the
Digox 6 .
NOTE:
If a flow volume outside this range is found, the
value indicating the flow will flash in the
"Measuring" screen, and an indicating symbol will
appear.
The accuracy of the flow measurement depends
on the viscosity of the medium.
4.2.2 Pressure
The pressure of the sample does not influence the
measured value. The measuring system of the
Digox 6 has been designed for operating
pressures of up to 8 bar, allowing for short
pressure peaks of up to 16 bar.
4.2.3 Temperature
The measured value is influenced by the
temperature with a gradient of 3% per °C.
The Digox 6 has got a temperature compensation
in the range between 0 and +50 °C.
4.3 Calibrating of the flowmeter
The calibration of the flowmeter is done in the
works with water. When taking the unit into
service, the Digox 6 should be calibrated with the
measuring medium.
When calibrating the flowmeter , the Kf factor is
determined. Usual values are between 0.9 and
1.2.
Calibration does not have to be repeated in
regular intervals. We recommend one-year
intervals.
4.3.1 Preparation
Required means
•
Measuring cylinder, 250 ml (included in the
supply)
•
PVC hose (included in the supply)
1. Connect the sample supply (marker In) to the
sampling point.
2. Connect the PVC hose to the sample return
(marker Out).
3. Switch the Digox 6 on and wait until the
"Measuring“ screen appears.
4. Set the flow at the regulating valve to 10 litres
per hour, check the measured value in the
display.
5. Press
.
The calibration menu is opened. Use the
cursor keys to mark the menu item
FLOWMETER.
6. Press
. The following display appears.
Figure 4.2