Campbell Scientific CS451/CS456 Pressure Transducer - Manual (Page 19)

CS451/CS456 Submersible Pressure Transducer
7.1.3 Appropriate Water Depth
The CS451/CS456 must be installed below the water at a fixed depth. This
depth should be chosen so the water pressure will never exceed the
transducer’s pressure range (twice its pressure range).
The output reading will not be correct, and the transducer
can be damaged if pressure is excessive (2 x full scale).
Pressure can be converted to feet of fresh water using the following simple
equation:
1 psi = 2.31 feet of water
For example, the maximum depth with a pressure range of 0 to 7.25 psig is
16.748 feet of water.
7.1.4 Dislodging Bubbles
While submersing the transducer, air bubbles may become trapped between the
pressure plate and the water surface, causing small offset errors until the
bubbles dissolve. Dislodge these bubbles by gently shaking the CS451/CS456
while under water.
If bubbles are not removed by rotation and shaking
underwater (or bleeding out the air in a closed system), the
CS451/CS456 reading will drift lower by the distance of the
gap as the bubbles are slowly dissolved into the water over
time.
Hitting against the well casing or other solid surface could
damage the transducer.
7.2 Installation Procedure
7.2.1 Lower to depth
Lower the transducer to an appropriate depth.
Do not drop the instrument or allow it to “free fall” down a
well as this may damage the sensor.
With long drops, it may be necessary to use the weighted nose cone
(option -WN).
7.2.2 Secure the Transducer
7.2.2.1 Tie Wrap/Tape
The transducer body can be strapped with tie wraps or tape. Campbell
Scientific offers cable ties (pn 7421) that can be used to secure and strain relief
CAUTION
CAUTION
CAUTION
CAUTION
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