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General Information
2.5.1 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 Flow Meter.
Safety Information
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