Important Notes For Installation And Operation - Sika Turbotron VT 20-Serie Betriebsanleitung

Important notes for installation and operation

For precise measurement, the length of the in- and outlet tubes must be observed
( § 3 "Important notes for installation and operation").
The inner diameter of the in- and outlet tube must correspond with the inner diameter of
the turbine flow sensor.
The flow medium to be monitored should preferably contain as few solid particles as pos-
sible. Present particles must not exceed a diameter of 0.63 mm. If necessary, install a
screen filter.
Avoid absolutely the formation of gas bubbles or cavitation in the medium by taking prop-
er measures.
The material of the instrument is not suitable for monitoring oils. The strength of the
used plastic parts would be considerably reduced.
In order to clean the flow sensor of contaminations, flush the unit reverse to the flow di-
rection ( § 7 "Cleaning of Turbotron").
Suitable measures should be taken to prevent the medium from freezing.
Blowing out the VT...20 can damage the turbine bearing.
Never blow them out with compressed air.
We recommend using only shielded connection cables, whereby the shield must lie on
one side (on the side of the wire ends) to ground.
Attention:
The union nut of the transducer is sealed and must not be opened!
Special safety instructions:
Warnings that are specifically relevant to individual operating procedures or activities can be
found at the beginning of the relevant sections of this operating manual.
3 Important notes for installation and operation
Observe the following instructions in order to achieve highest-possible measurement accu-
racy and specified output signal:
•
Before installing the turbine flow sensor, flush the pipe carefully. You avoid a blocking of
the turbine caused by particles from the pipe installation.
•
The flow sensor can be installed in any position. If it is installed in vertical pipes, the di-
rection of flow from bottom to top is to be preferred. You must absolutely avoid a free
outlet.
•
The arrow which is placed on the flow sensor () shows the only permitted flow direc-
tion.
•
In order to achieve the best measuring accuracy, a "straight" inlet section of at least
10 x DN must be maintained in front of the flow sensor. A "straight" outlet section of
5 x DN must be taken into account after the flow sensor.
The inner diameter of the inlet and outlet section must correspond to that of the flow
sensor. The pipe can be constricted or widened in front of and behind it.
In practice, compliance with these rules is often not possible. This influences the pulse
rate and measurement accuracy.
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VT...20