ATS 2140-M Series, Инструкция по эксплуатации

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8.2.4 Extensometer Cautions
CAUTION: Do not use extensometer at a temperature above the rating of the extensometer.
There is a standard temperature rating of 1100 degrees Celsius for most extensometers
manufactured from Inconel 600/601 materials.
CAUTION: Do not install extensometer in any manner that could damage the extensometer if
specimen failure occurs. For example, avoid limited clearance and restrictive movement.
CAUTION: The displacement transducers should extend far enough below the oven or furnace
so as not to be damaged by heat.
8.2.5 Extensometer Calibration
Each extensometer must be calibrated in the channel in which it is to be used. In practice, the LVDT or
other transducer remains attached to the signal conditioner board in the system console. In this manner,
the inadvertent switching of transducers is avoided.
There are two distinct, but similar functions available to the operator to ensure proper operation
and accuracy of the extensometer: Calibration and Verification. Both involve using a micrometer to
increment the LVDT in precise amounts through its range of operation, but they differ in the way the
signal is handled by the system.
8.2.5.1 Calibration
In the Calibration function, a polynomial curve fit is used to effectively ensure that the device is linear,
allowing much greater accuracy of operation. In this process, the calibration device is assumed to be
perfect and the output signal is corrected to a straight line, against which the data will be compared
to produce strain information. In the verification process, the LVDT is again incremented through its
range using a precise micrometer and the resulting output is compared to the original. After correcting
for non-linearity, any difference is presumed to be error and the extensometer is graded based on the
result. It is important, therefore, to run the verification process frequently, since this is the true check of
extensometer performance.
A System Calibration Report can be found by choosing Calibration from the System pull-down under the
View menu. Other calibration reports can be found under the Calibration menu.