Thermo Scientific HB-S200, User Manual

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Sarasota 200 Ultrasonic Multipath
Flowmeter
Section 2, SYSTEM COMPONENTS, Page 2-11 Thermo Fisher Scientific
SYSTEM COMPONENTS
2.4.3 500 kHz transducers
For use with path lengths above 10 metres. In cases where serious attenuation is anticipated
(for example, sewage) it is recommended that 500 kHz transducer be used above 5 metres.
At the upper end, they may normally be used up to 80 metres. For cases where serious
attenuation is anticipated, lower frequency transducers should be used for paths above 50
metres.
The 500 kHz transducers have the HT and signal amplifiers built in. They are connected
directly to the flowmeter or via star boxes. If ultrasonic depth transducer(s) are being used, it
is usual to use 500 kHz frequency when that frequency is being used for water velocity
measurement.
The transducers are supplied with 5 metres of cable which is connected to a star box or
extended to run directly to the flowmeter. Coaxial cables to the flowmeter enclosure are
usually made up on site. Cables may be supplied to length if so ordered with made-up ends.
However, this often makes the installation more difficult where there is the need to pull cables
through ducts.
The 500 kHz transducer also has a temperature sensor built in allowing water temperature at
each transducer to be recorded by the Sarasota 200.
2.4.4 Lower frequency transducers
Consult Thermo Fisher Scientific about low frequency transducers for path lengths above 80
metres or where conditions might attenuate higher frequency signals.
If ultrasonic depth transducer(s) are being used, it is usual to use 500 kHz frequency when
lower frequency transducers are being used for water velocity measurement.
2.4.5 Maximum cable lengths
Item From To Max
length Comment
1 500 kHz transducer
(velocity or depth) Flowmeter 300 m Direct connection
2 1 MHz TBox
(velocity or depth)
Flowmeter 300 m Direct connection
3 Star box Flowmeter 300 m Multi-drop
(but see depth options items 6 & 7)
4 500 kHz transducer Star box 5 m Multi-drop
(but see depth option item 6)
5 1 MHz Tbox 1.5 m std. Longer separations may be supplied.
Consult factory.
6 Tbox Star box 5 m Multi-drop
(but see depth option item 7)
7 500 kHz depth transducer Star box 50 m Multi-drop depth option
(star box max 5 m from flowmeter)
8 1 MHz depth TBox Star box 50 m Multi-drop depth option
(star box max 5 m from flowmeter)
9 1 MHz IS Barrier Consult factory
10 Barrier Tbox 1 m