Troxler Enhanced RoadReader Plus 3451, Manual Of Operation And Instruction

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DRIFT TEST
If the gauge passes the stat test, but shows long-term drift between
measurements, perform a
drift test to check the long-term drift. A
drift test consists of five counts taken 3–8 hours after a stat test. The
gauge sets the pass/fail limits based on the percent difference
between the average of the stat test and drift test results. If the
percent difference exceeds 0.5 percent for density counts or 1
percent for moisture counts, the drift test
fails . If the drift test fails,
ensure that the gauge setup and testing were conducted correctly,
and take an additional test. If the second test fails, call the nearest
Troxler service center for assistance.
NOTE
The drift test consists of five 4-minute count, whereas
the stat test consists of twenty 1-minute counts.
Therefore, each test takes approximately twenty minutes
to conduct.
DO NOT turn the gauge off between a stat test and a
drift test. The stat test must be current. The gauge must
not be moved between the stat and drift tests to
eliminate possible failure due to positioning changes.
To access the Drift Test functions, press the
〈
Drift Test
〉
button on
the Diagnostics Menu (see Figure C–1). The PDA displays the
Drift Test Menu shown in Figure C–6.
Taking a Drift Test
With the gauge still in an area free of other nuclear gauges or
radioactive sources and on the reference standard block, press
〈
Take Drift Test
〉
. The PDA displays the date and time of the last
stat test and asks whether to continue with the drift test.
NOTE
If it has been less than four hours or more than eight
hours since the last stat test, then the gauge allows the
operator to exit the drift test. To exit and take another
stat test, press
〈
No
〉
at the prompt. To continue with the
drift test, press
〈
Yes
〉
at the prompt.
Model 3451 Appendix C–5
C.
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