Teledyne TIENet 350, Инструкция по установке и эксплуатации

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TIENet ® Model 350 Area Velocity Sensor
Section 2 Installation
2-9
2.5 Installing the 350 AV
Sensor
Prior to mounting the sensor in the flow stream, check the dis-
played level reading. In open air, the reading should be zero. If
not, adjust the level to zero from the Level Adjustment screen
(refer to “ Setting the 350 Ex Level ” on page 3-6).
Note
If the 350 sensor is part of the optional submerged functionality
for a LaserFlow system, the initial level setting is the measured
distance from the bottom of the channel to the bottom of the
LaserFlow sensor.
2.5.1 Installation
Considerations
See Section 2.5.2 for a summary of sensor mounting options for
round pipe installations. Sensor installation is discussed in detail
in ISCO’s Mounting Rings Instruction Manual , which explains
how to mount the 350 sensor in flow streams using spring rings,
scissors rings, a street level installation tool, and mounting
plates.
Several factors concerning installation may affect your system’s
performance. Please review the following to understand how to
obtain the best results:
Uniform flow - The 350 sensor provides the best results in flow
streams with uniform flow. An example of uniform flow is shown
at left.
Avoid poor channel conditions - Poor channel conditions may
cause incorrect or erratic readings. Areas to avoid are:
• Outfalls or channel intersections
• Flow streams at very low levels with high flow rates
• Turbulence
• Channel sections that are apt to collect debris or silt
• Depths that consistently run below 25 mm (1 inch)
The 350 sensor can detect levels above approximately 1.0 cm
(0.4 inch) and typically can measure velocities in streams as low
as 25 mm (1 inch). Streams that run consistently below 1 inch
are not a good application for the 350 sensor.
The example at left shows a few of these poor conditions. The
outfall is drawing down the liquid level and the 350 sensor is dis-
turbing the flow. In this example, the 350 sensor should be
moved forward to avoid the drawdown near the outfall.
Liquid properties - Velocity measurements depend on the
presence of some particles in the stream, such as suspended
solids or air bubbles. If the stream lacks particles, it may be nec-
essary to aerate the water upstream from the sensor.
Handle with care - Abusive handling will damage the 350
sensor. Although the 350 sensor will survive normal handling
and installation, treat the sensor with reasonable care. The
internal components cannot be repaired.
Ideal Conditions - Uni-
Poor Conditions