Teledyne 4250, Installation And Operation Manual, Page: 17 / 204

4250 Flow Meter
Section 1 Introduction
1-5
The third type of area-velocity sensor is the low-profile probe.
This probe is streamlined for use in shallow flows and small
pipes, in depths as low as 1 inch (25 mm).
The area-velocity sensor is designed to avoid accumulating
debris that could affect readings. In rare instances, however,
debris may accumulate inside the opening containing the
pressure transducer and cause it to give false readings. In such
cases, you may need to remove the probe and clean it.
Figure 1-3 Low-Profile Area Velocity Probe
Figure 1-4 Operation of the Area Velocity Sensor
Low Profile Sensor
Particles or
Air Bubbles
Flow
Area Velocity
Sensor