Measurement Setup - Flow - Vega VEGAPULS C 21 Operating Instructions Manual

Agitators
Foam generation
VEGAPULS C 21 • Two-wire 4 ... 20 mA/HART
If there are agitators in the vessel, a false signal 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.
Fig. 15: Agitators
Through the action of filling, stirring and other processes in the vessel,
compact foams which considerably damp the emitted signals may
form on the product surface.
If foams lead to measurement errors, you should use the biggest pos-
sible radar antennas or sensors with guided radar.
4.4

Measurement setup - Flow

In general, the following must be observed while mounting the sensor:
•
Mounting the sensor 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 accu-
racy: 250 mm (9.843 in)
Detailed project planning data can be found at the channel manufac-
turers and in the technical literature.
The measurement can be individually configured for the respective
flume via a PC/notebook and PACTware/DTM.The measurement can
be individually configured for the respective flume via a PC/notebook
and PACTware/DTM.
The following examples serve as an overview for flow measurement.
At smaller distances the measuring accuracy is reduced, see Technical data.
1)
1)
4 Mounting
15