Checkline TI-25PX, Руководство по эксплуатации

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The transducer must be used correctly in order for the TI-25PX to produce accurate,
reliable measurements. Below is a short description of the transducer, followed by
instructions for its use.
This is a bottom view of a typical transducer. The two semicircles of the wear face
are visible, as is the barrier separating them. One of the semicircles is responsible for
conducting ultrasonic sound into the material being measured, and the other semicircle
is responsible for conducting the echoed sound back into the transducer. When the
transducer is placed against the material being measured, it is the area directly beneath
the center of the wear face that is being measured.
This is a top view of a typical transducer. Press against the top with the thumb or index
finger to hold the transducer in place. Moderate pressure is sufficient, as it is only
necessary to keep the transducer stationary, and the wear face seated flat against the
surface of the material being measured.
Measuring
In order for the transducer to do its job, there must be no air gaps between the wear-
face and the surface of the material being measured. This is accomplished with the use
of a “coupling” fluid, commonly called “couplant”. This fluid serves to “couple”, or
transfer, the ultrasonic sound waves from the transducer, into the material, and back
again. Before attempting to make a measurement, a small amount of couplant should
be applied to the surface of the material being measured. Typically, a single droplet of
couplant is sufficient.
After applying couplant, press the transducer (wear face down) firmly against the area
to be measured. The Stability Indicator should have six or seven bars darkened, and a
number should appear in the display. If the TI-25PX has been properly “zeroed” (see
page 12) and set to the correct sound velocity (see page 16), the number in the display
will indicate the actual thickness of the material directly beneath the transducer.
If the Stability Indicator has fewer than five bars darkened, or the numbers on the
display seem erratic, first check to make sure that there is an adequate film of couplant