Face Dipstick 2200 Series, Руководство оператора

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Appendix E - Test Track
E-2
6. Tap the “Close” button on the top right of the graph, select the run you just collected, and use
CALCULATE/BIAS.
7. The Bias should be small, between 0.0005 and 0.002, but
certainly not more than 0.003. The value of the Bias will
depend on the surface texture of the floor you are walking
on, as well as how clean it is. Smoother texture, less dust =
smaller Bias. More texture (like a sidewalk) and/or more
dust, grit, etc, on the floor = higher Bias. The Bias should
always be positive, not negative, unless it is very small, less
than 0.0005.
8. Now use REPORT/GRAPH to look at it again. The profile will start and end at 0.00", and it will be
symmetric about the 50-ft point. It may look like a butterfly or a gull-wing, or just sloped one way
and then back up. Whatever it looks like, the left half will be a mirror image of the right half. The
fact that it is symmetric shows you that the Dipstick is collecting the data exactly the same out and
back.
9. Now Re-select the same Run, then use EDIT/TEST TRACK. This will break the Run into two halves.
To facilitate comparison between the two halves, the program will automatically reverse the second
half of the Run so it also starts at the starting point and runs out to the place where you turned around.
10. Now select both of the 50-ft runs and use REPORT/GRAPH to show both of them together. They
should ideally form a single line, with one of the Runs overlapping the other line. If the lines do not
overlap completely, it may be that for some distance, you did not walk precisely on the line.
Note how the two runs overlap each other. Since you are now showing only the first half of the run, it
will no longer end at an elevation of zero. (The end point elevation is the elevation of the 50-ft point.)