Troxler 3430 Plus, Руководство по эксплуатации и инструкции

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Model 3430 Plus & 3440 Plus 2–5
CALIBRATION
Troxler calibrates the gauge at the factory and recommends that it
always be calibrated by an authorized Troxler service center. For a
list of Troxler and authorized Troxler service centers, refer to page
iii of this manual or visit the Troxler website at
www.troxlerlabs.com/SERVICES/services.shtml.
The operating range of the gauge is from 1100 to 2700 kg/m
3
(approximately 70 to 170 pcf).
OFFSETS
The factory calibration provides accurate results for the majority of
materials encountered in construction. If the gauge is to be used to
test materials not covered by the factory calibration, the readings
can be adjusted using an
offset .
Perform a density offset if the test material is outside the density
range for average soil or if the material composition varies from
average soil/asphalt. Perform a
moisture offset if the test material
contains hydrogenous materials (other than water) or materials that
absorb neutrons. Materials such as cement, gypsum, coal, mica, and
lime all contain chemically bound hydrogen that will cause the
gauge to display a moisture content that is higher than actual.
Material such as boron and cadmium are neutron absorbers and will
cause the gauge to display a moisture count that is lower than actual.
Vertical structures scatter neutrons and gamma photons back to the
gauge. This could result in inaccurate moisture and density readings.
To take readings in a trench or within 0.6 m (2 ft) of a large vertical
structure, perform a
trench offset .
2. T
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