2018-05-09
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in downstream direction
3 x DN. For flow sensors DN50 and smaller the straight pipelines installation in upstream and downstream are not
necessary.
Avoid installation of the flow sensor near the pumps due to the risk of cavitation. The flow sensor can be mounted horizontal, vertical or inclined
position on a supply or return pipeline. However the horizontal or inclined installation is allowed only when the working medium flows from
bottom to top. The location and position of the flow sensor from DN25 to DN100 must be selected in way that is reducing the risk of air bubbles
accumulation in the zone of ultrasonic flow sensor (see Fig. 5.13).
a) Permissible installation position.
b) The prohibited installation position (air bubbles may gather).
Fig. 5.13 Mounting position of DN25-DN100 flow sensors.
Flanged connections require proper sizing of the gaskets matching the piping diameter. During installation gaskets must exactly align with the
centre of the pipe cross-section to avoid gasket protrusion into the piping passage that could obstruct the flow.
Before installing the flow sensor, rinse the pipeline well mounting spacer instead of flow sensor for the time of flushing.
Proper performance of the meter requires that the pipeline was pressurized, completely filled with the working medium and the flow direction
shown by the arrow on the flow sensor body (see Fig. 5.14.) must match the actual flow in the metering circuit.
Fig. 5.14. The flow direction marking according to which flow sensor must be mounted.
It is forbidden to wire flow sensor signal cables less than 5 cm away from wires or power cables of other devices.
5.3.3. Mounting of temperature sensors
The temperature sensors are mounted by head upwards, in perpendicularly to the pipe axis or inclined by 45° angle to the pipe position, so the
temperature sensor tip reaches or crosses beyond the pipe axis (see Fig. 12.6.).
For meters with G¾" and G1" connections it is possible to mount one temperature sensor directly in the flow sensor body.
5.4. Setting up the jumper
The jumper pin connector is on the calculator PCB, between the temperature sensor screw terminals and the pulse input/output screw terminals
(see Fig. 10.1.). Joining and opening the appropriate connector pins with the jumper lets you switch between the normal operating mode and
the test mode of the meter, or transform pulse outputs into pulse inputs (see
