Campbell CS475, Инструкция по эксплуатации

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CS475, CS476, and CS477 Radar Water Level Sensor
11
7. Installation
If you are programming your datalogger with Short Cut , skip Section 7.3 ,
Wiring to Datalogger
(p. 14)
, and Section 7.4 , Datalogger Programming
(p. 14)
.
Short Cut
does this work for you. See Section 4 ,
QuickStart
(p. 2)
, for a
Short
Cut tutorial.
7.1 Site Selection
1. Mount the sensor high enough to prevent submersion during flooding
conditions.
Since the sensor is commonly installed over water from
tall structures, use appropriate safety equipment such
as a safety harness or a life preserver when installing or
performing maintenance on the sensor.
2. Install the sensor above the smoothest part of the water surface.
The smoothest part of the water surface is typically found halfway
between bridge piers. However, bridges with long spans between
the piers experience more vibration. For these bridges, vibration
can be minimized by mounting the sensor a quarter to a third of
the distance to the next pier.
3. Avoid mounting near horizontal structural surfaces such as beams,
brackets, and sidewall joints because these surfaces reflect a strong signal.
If these structures cannot be avoided, use the
False Echo Learn
command
to map out the interfering structures in the beam profile (see Appendix
C.1.3 , Start False Echo Learn
(p. C-3)
).
4. Center the sensor beam a minimum of 2.5 m from any obstruction in the
measurement range. Obstructions to be aware of include excessive waves,
splashing, pipes, wires, and logs. The radiation beam spreads as it leaves
the sensor (see TABLE 7-1 and TABLE 7-2 ).
Usually the beam path is 10° for the CS475, and 8° for the
CS476/CS477.
5. Be aware that bridges contract and expand with temperature changes.
Traffic loads or trucks can also cause changes to the bridge height.
6. Do not install the sensor where submerged obstructions such as rocks or
bridge piers can distort or disturb water level.
7.2 Mount and Align the Sensor
1. Choose an appropriate site away from obstructions and over the smoothest
part of the water (see Section 7.1 , Site Selection
(p. 11)
).
2. Center the sensor beam a minimum of 2.5 m from any obstruction in the
measurement range. Obstructions can include excessive waves, splashing,
WARNING
NOTE
NOTE