Hach Sigma 950, Инструкция по эксплуатации инструмента

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Sensor Installation
b. Measure the depth from the bottom of the bucket to the surface of the water (D1)
(
Figure 10 ) and enter the value using the numeric keypad. Press
ACCEPT
to
continue.
Figure 10 Measuring Submerged Depth, Horizontal Orientation
6.6 Bubbler
The 950 Bubbler Flow Meter utilizes the bubbler method of level measurement. A length
of tubing is placed in the flow stream at the proper location for head measurement. A small
amount of air is continuously pushed through the tubing and bubbles slowly come out the
end. The pressure in the tubing changes in proportion to the liquid level in the flow stream.
The 950 Flow Meter reads the this pressure and converts it to a level reading. The 950
Flow Meter will accurately measure the level in the channel as long as the end of bubbler
line remains below the zero level point of the channel. After measuring the level, the 950
microprocessor converts the level reading to a flow rate based on the user defined
characteristics of a primary device.
6.6.1 Bubbler Connections
Note: Note: To connect a level-only bubbler, push the
1
/
8
” I.D. vinyl tubing (P/N3807) onto the
bubbler line port and the other tubing end in the flow stream.
The Depth Only and bubbler Area/Velocity Sensor connector, bubbler line connection, and
air dryer canisters are located on the right side of the flow meter. A small diameter tube is
contained within the sensor cable to supply air from the
950 Flow Meter to the sensor in the flow stream. See
Figure 11 .
Figure 11 Bubbler Connections
Three ports on the 950 Flow Meter pertain to air flow for bubbler operation:
• Intake Port —This port supplies fresh air to the internal air pump. The air is drawn
through a dryer tube consisting of two hydrophobic filters and a desiccant material that
removes moisture and dirt from the incoming air.
D
1
1 Right-side of 950 meter 2 Bubbler line connection 3 Velocity connection
1
2
3