Campbell CRS451, Руководство пользователя

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User Manual
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the water body is at risk of freezing solid, placing the sensor in a stilling well that
extends below the frost line will protect the sensor from freezing water.
6.3 Dislodge Bubbles
While submersing the CSR451/CRS456, air bubbles may become trapped inside
the nose cone, causing small, offset errors until the bubbles dissolve. Dislodge
these bubbles by gently shaking the CRS451/CRS456 while under water.
Hitting the instrument against the well casing or other solid
surface could damage the CRS451/CRS456.
If the bubbles are not removed by rotation and shaking
underwater (or bleeding out the air in a closed system), the
CRS451/CRS456 reading will drift lower by the distance of
the gap as the air is slowly dissolved into the water over time.
6.4 Well Installation
Braided stainless steel cable (pn #29221-L) is used to lower the instrument to an
appropriate depth and to suspend the CRS451/CRS456 in a well.
With long drops, it may be necessary to use the weighted nose cone (option
–WN).
For surface installations the instrument’s body can be strapped with tie wraps or
tape. Campbell Scientific offers cable ties (pn #7421) to secure the cable. If
installing in a well, fasten the cable to the well head.
6.5 Other Installations
The CRS451/CRS456 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.
6.6 Battery Voltage Reading
The voltage of the lithium ion battery used in the CRS451/CRS456 will abruptly
decrease at the end of the battery’s useful life, which makes predicting remaining
battery life difficult by measuring battery voltage alone. Knowing the energy
consumption of the CRS451/CRS456 while in operation, HydroSci displays a
predicted remaining battery life by combining an estimate of the energy consumed
based on the totalized measurements since new and direct battery measurements.
For this reason, if the battery is removed from the CRS451/CRS456 anytime
during deployment and then replaced, HydroSci will assume a fresh battery was
added to the device and the estimated remaining battery life will be overstated.
For similar reasons, if the operating system is upgraded or sent to the
CRS451/CRS456, the estimated remaining battery life will also be exaggerated by
HydroSci.
CAUTION
CAUTION