Principle Of Operation - GF PF220 V2 Betriebsanleitung

Design and function
3.3

Principle of operation

The flowmeter takes accurate flow measurements by determining the difference between the transmission times of two ultrasonic
signals.
A periodic voltage pulse acts on the transducer crystals and produces an ultrasonic beam at a
certain frequency. The beam is first transmitted by the downstream transducer (blue) to the
upstream transducer (red).
The beam is then sent in the opposite direction, i.e. from the upstream transducer (red) to the
downstream transducer (blue). The time taken for the ultrasonic to pass through the liquid in this direction is slightly shortened by
the speed at which the liquid flows through the pipe.
The resulting time difference T1 – T2 is directly proportional to the speed at which the liquid flows through the pipe.
In addition to the flow rate, a flowmeter with heat meter option measures the temperature difference between the flow and return
of the system via two PT100 temperature sensors.
The difference in temperature between the flow and the return, in combination with the volume of water that has passed through
the system, is used to calculate the energy difference in the medium.
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T1
=
T1-T2=m/s
T2
=
Principle of
Operating Instructions