Hach Sigma 950, Инструкция по эксплуатации инструмента

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Programming Features
B.15.1 Keypad Test
Keypad Test provides a simple means of verifying the operation of all front panel keys.
Selecting
KEYPAD TEST
from the diagnostics menu will bring up the following screen:
Pressing any key on the front panel (except for the upper left soft key) will cause that key
label to appear in the center of the display. All numeric keypad keys, soft keys, and
function keys may be tested in this manner. To end, press
QUIT
(this also verifies the
upper left soft key operation).
B.15.2 LCD Test
LCD Test verifies all the pixels in the Liquid Crystal Display (LCD) are functional. The
LCD is made up of 14,400 pixels that are turned on and off as needed to create the
display of graphics and text. Each individual pixel is turned on and off by its own
transistor. If a transistor fails, the pixel will not turn on, potentially causing an unreadable
or confusing display.
Select
LCD TEST
from the Diagnostics Menu. The display will become black for 3
seconds to verify that all pixels are functional. A defective pixel will stand out as a white
dot in the field of black dots. A message, “THE DISPLAY WILL REMAIN INVERTED FOR
3 SECONDS” is shown for 2 seconds followed by a 3-second period with all dots turned
on.
B.15.3 Demonstration Graph
The demonstration graph provides a small portion of demonstration data to use when
learning how to use the graphing screen for the first time or for training others on its
operation. No data logging is required to use the demonstration graph.
B.15.4 Velocity Analysis
A velocity probe must be installed in the flow stream and must be connected to the meter
in order for this diagnostic to work. This diagnostic allows the viewing of ‘real time’
readings directly from the Submerged Depth/Velocity Probe. It shows the current velocity
Signal Strength (percentage of Doppler signal returning to the probe) and a ‘real time’
velocity measurement of the flow stream. Use this diagnostic to determine that the probe
is mounted for optimal velocity measurement. The closer to 100% the Signal Strength is,
the more stable the velocity reading will be. If the signal seems low (50% or less), it may
be due to improper installation of the probe or a lack of particulate in the flow stream.
11:00 AM 21 - APR - 01 KEYPAD TEST
QUIT
KEY PRESSED:
5
PRESS ANY KEY
11:00 AM 21 - APR - 01 VELOCITY ANALYSIS
SIGNAL STRENGTH: 90%
VELOCITY: 7.00 fps
RETURN