Campbell CS451, Инструкция по эксплуатации

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CS451/CS456 Submersible Pressure Transducer
7.2 Installation Considerations
The CS451/CS456 is designed for water level measurements. Typical
applications include agricultural water level/flow, water wells, lakes, streams
and tanks. If the device is to be installed in a liquid other than water or in
contaminated water, check the compatibility of the wetted material. The
CS456 should be used in harsh water applications, including salt water.
7.2.1 Non-Vertical Installations
The CS451/CS456 can be installed in any position; however, when it leaves the
factory it is tested in the vertical position. There will be an offset error if not
installed vertically; contact Campbell Scientific for more information.
Strapping the transducer body with tie wraps or tape will not hurt it.
7.2.2 Offset Calculation
The pressure created is directly proportional to the water column above the
sensor. An offset is used to correct the final measurement to any error due to
sensor zero offset or installation.
For example, if the correct elevation of the water, as measured by a staff gauge
or other measurement device, is 2015.50 feet, and the CS451 provides a
reading of 5.76 psig, then:
5.76 psig * 2.31 ft/psig = 13.3056 ft.
So, the offset is calculated:
2015.50 ft – 13.3056 ft = 2002.1944 ft
This offset can be accounted for in the program instruction of the SDI-12
recorder.
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