Milltronics InterRanger IR-200, Инструкция по эксплуатации

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InterRanger IR-200 16 PL-545
DETERMINING TANK DEPTH
The graph that appears in the LCD display shows numbers
along its side indicating depth in feet. A peak appearing at
any place on the display indicates an interface at that
depth. The larger the peak, the stronger the echo returned
and the more distinct the interface.
For example, if we are measuring a tank with a 12 foot
depth we would initially test the unit with a TANK DEPTH
setting of 14 feet. This setting will give us a strong echo at
12 feet (Figure 1).
At this point there are two ways of determining the TANK
DEPTH:
From the Test Echo Profile
Look at the profile displayed and check for a large peak on
the graph where you would expect the bottom to be. Write
down this number so that it can be entered later. This is the
easiest method of determining the tank depth but it can be
in error if there are thick solids at the bottom of the tank
which return a strong echo.
Physical Measurement
If the bottom is not visible on the graph, or no major peaks
appear where expected, this usually means that the solids
are very thick on the bottom or that the tank bottom is
sloped. In this case carefully measure the distance between
the Sensor face and the bottom of the tank to obtain your
TANK DEPTH measurement. This is the preferred method
of measurement because it is the most accurate.
In the example we then change the TANK DEPTH to 12
feet (your value is determined by your tank depth and
sensor placement). The InterRanger IR-200 now takes the
next-largest peak and scales it to 80% of the chart range
(Figure 2). In the example this peak is at the 8 foot mark
and is most likely the interface of interest for us. This
automatic scaling is only available if the GAIN CONTROL is
set to 0. (See GAIN CONTROL on page 25.)
If the graph is a flat line with GAIN=100% (Figure 3) then
there is a problem in the wiring, the Sensor placement, or
tank conditions are completely upset and no interface can
be detected.
Figure 1 – Detection of tank bottom at 12 feet
Figure 2 – Detection of interface at 8 feet
Figure 3 – Error condition