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UMPIOXR400V2-7-1EN, 2012-07-01
5 Selecting the Measuring Point
Install the sensor head so that the direction of flow is parallel to the prism edge (see Fig. 5.2).
Fig. 5.2: Orientation of measuring prism in pipe
To prevent deposits from forming on the measuring prism, ensure the following conditions:
•
permanent minimum flow in the pipe
•
the pipe diameter is relatively small at measurement point, i. e., the smaller the pipe diameter, the larger the
pressure and the larger the self-cleaning effect
•
the fluid temperature is relatively high but within the specifications of the sensor, i. e., if the temperature
increases, the fluid solubility increases but the viscosity decreases
•
the fluid pressure is relatively high but within the specification of the sensor, i. e., as the pressure increases, the
fluid solubility increases and fewer gas bubbles form
If necessary, clean the measurement prism manually. Therefore, choose a measuring point where the flow can be
interrupted and the sensor can be installed/removed without difficulty.
The selected measuring point should be easily accessible for service work.
Make sure that the transmitter is installed within the range of the cable. The ambient temperature at the installation
site must be within the operating temperature range of the transmitter.
Note!
Protect the sensor against direct sunlight, rain and vibrations (pumps).
Note!
If the fluid is highly viscous, abrasive or contains solids in suspension, a bypass is recom-
mended.
Attention!
Never wrap the cables (extension and sensor cables) around hot pipes.
flow direction
