Thermo Scientific HB-S200, Руководство пользователя

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Sarasota 200 Ultrasonic Multipath
Flowmeter
Section 1 INTRODUCTION Page 1-8 Thermo Fisher Scientific
INTRODUCTION
Water level
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Levels are combined in the following algorithm:
Only non-faulty measurements are used.
Highest and/or lowest are discarded until 3 remain.
The one furthest from the others is discarded leaving 2.
The remaining 2 measurements are averaged for arbitrated level if within an
acceptable band defined via the PC GAFA software.
If they are not within the acceptable band, level determination fails and flow cannot
be calculated.
If only 1 level measurement is installed or only 1 remains after arbitration, it is used
as the arbitrated level.
If not OK, level fails and flow cannot be calculated.
•
Levels defined as valid but rejected by the algorithm will be indicated on the level status.
•
Where the flowmeter is installed in a closed conduit which always runs full, the channel
shape is entered in the usual way but there is no need for a level measurement. The
flowmeter is programmed with a fixed level input corresponding to the top of the conduit.
Transducer and bed levels
All heights may be set to a fixed datum (local or national) or relative to mean bed level. The
former requires a height for the bed and avoids re-entering all path and level transducer
heights in the event of a change to the bed.
General
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“Instantaneous” means the average over the cycle time scale. This defaults to 10
seconds for fast response suitable for small channels. It may be set to 1 minute for
smoother averaging where the rate of change of flow conditions is slower.
•
The average period is the time over which measurements are averaged for the purpose
of output or logged data. The average period cannot be shorter than the cycle time.
•
At the data logging intervals, the averaged values of the selected data are stored.
•
Analogue inputs will normally be linear. However, non linear characteristics may be
entered via the PC, see Appendix 1
•
When operating on a 12 volt source, for example from a solar panel, power saving is
possible by using intermittent operation. Power consumption in normal and intermittent
modes is quoted in the Appendix 2: Specification.