Hach 910, Инструкция по эксплуатации инструмента

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Section 1
Page 17
GettingStarted.fm
Choosing the Appropriate Meter and Sensor Combination
1.4.1 Types of Sensors
Submerged Depth/Velocity Sensors
Submerged Depth/Velocity sensors can measure level and velocity
simultaneously. A submerged pressure transducer measures level. Velocity is
measured with sound waves, using the Doppler principle.
Wafer Velocity Sensor
The Wafer Velocity Sensor (Cat. No. 88005 or 88006) is an extremely low-
profile velocity sensor. It does not measure level. The streamlined shape of
the wafer probe allows velocity measurement in very low-flow conditions.
When used in conjunction with a level sensor (such as the In-Pipe Ultrasonic
Level Sensor), you can calculate flow.
In-Pipe Ultrasonic Sensor
Use the In-Pipe Ultrasonic Level Sensor (Cat. No. 3702-01 or 3702-02) in
pipes where level measurement to the top of the pipe is desired. This sensor
has no effective deadband and will read the level until liquid reaches the
bottom of the sensor housing. The entire deadband is contained horizontally
within the sensor body.
Ultrasonic Sensor (Downlook)
Downlook ultrasonic sensors are available with different beam angles,
beam spread, and deadbands. Use the 75 KHz sensor with the 920 or 930
Flow Meter.