Thermo Scientific HB-S2000, Руководство пользователя

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Sarasota 2000 Ultrasonic Multipath
Flowmeter
Section 1 INTRODUCTION Page 1-8 Thermo Fisher Scientific
INTRODUCTION
there is a small possibility of confusing a signal reflected back to the firing transducer with
one received from the opposite transducer.
Water level
•
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 on screen C20: Channel Configuration.
If not, level determination fails and flow cannot be calculated.
If only 1 level measurement is installed or only 1 is not discarded, 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,
screen C10: Instantaneous Flow & Level.
•
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 as though it had an encoder level input (section 2.3.3.2.3) with
a reference level at the top of the conduit and a cal. factor of zero.
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
•
“Instantaneous” means the average over the cycle time scale. This defaults to 10
seconds but may be set to 1 minute for large numbers of paths or long path lengths via
screen S22: Station Configuration.
•
The average period is the time over which measurements are averaged for the purpose
of output or logged data. If the cycle time is set to 1 minute, the average period cannot be
shorter.
•
At the data logging intervals, the averaged values of the selected data are stored.
•
Analogue inputs will normally be linear. However, screen C212: Analogue Input allows
non linear characteristics to be entered.
•
When operating on an external 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 3:Specification
•
The LCD display will turn off 15 minutes after the last keyboard operation. This is to
reduce power and prolong LCD life. Pressing any key will turn it on again.