Siemens SITRANS LR140, Руководство по эксплуатации

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Installing/mounting
4.3 Measurement setup - Flow
Agitators
If there are agitators in the vessel, a auto false echo suppression should be carried
out with the agitators in motion. This ensures that the interfering reflections from
the agitators are saved with the blades in different positions.
Figure 4.9 Agitators
Foam generation
Through the action of filling, stirring and other processes in the vessel, compact
foams which considerably damp the emitted signals may form on the medium
surface.
If foams lead to measurement errors, you should use the biggest possible radar
antennas or transmitters with guided radar.
4.3 Measurement setup - Flow
In general, the following must be observed while mounting the device:
• Mounting the transmitter on the upstream or inlet side
• Installation in the centre of the flume and vertical to the liquid surface
• Distance to the overfall orifice or Venturi flume
• Min. distance to the max. height of damming for optimum accuracy: 250 mm
(9.843 in)
1
Detailed project planning data can be found at the channel manufacturers and in the
technical literature.
The following examples serve as an overview for flow measurement.
1
At smaller distances the measuring accuracy is reduced, see "Technical data".
SITRANS LR140
Operating Instructions, 08/2020, A5E50352144
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