Campbell CS451, Инструкция по эксплуатации

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CS451/CS456 Submersible Pressure Transducer
4.3 Step 3 — Dislodge 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.
CAUTION
Hitting against the well casing or other solid surface could
damage the transducer. CAUTION
4.4 Step 4 — Install Transducer
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.
CAUTION
With long drops it may be necessary to use the weighted nose cone (option
-WN).
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
the cable. If installing in a well, fasten the cable to the well head. Wrap the
cable ties around the cable jacket.
Never suspend the CS451/CS456 from the connections at
the top of the cable. Sharp bends or excessive pinching of
the cable can cause damage and may pinch off the vent
tube causing measurement errors. CAUTION
Several readings should be taken to ensure proper operations after installation.
4.5 Step 5 — Measure Initial Water Elevation
Use a staff gauge (or other device) to measure the initial elevation of water.
This value is used to calculate an offset that corrects the final measurement for
errors due to zero offset or installation. SCWin will make the offset
calculation. Refer to Section 7.2.2,
Offset Calculation , if not using SCWin to
calculate the offset.
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