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measurement failure, but it also causes excessive transducer wear.
The transducer should be inspected periodically for signs of uneven
surface wear. If the surface of the transducer is worn on one side more
than another, the sound wave traveling through the material may no
longer be perpendicular to the material surface. In this case, an
accurate measurement cannot be made.
Holding the Transducer
Press the top of the transducer using thumb or index finger when
measuring. Press the transducer properly and keep the position so
that the transducer maintains contact with the surface.
Propagation of Ultrasonic Wave
The sound velocity is easily influenced by the temperature, state of
stress and other physical properties. There are some materials whose
sound velocities vary based on the kind of ultrasonic wave and the
direction of travel.
Shape of the Transducer
The appropriate transducer should be selected in accordance with the
geometric shape of the measurement area. In this case, it is
necessary to select the size of the transducer. Connect the transmitter
plug and the receiver plug to the coaxial connectors on the main unit.
The plugs can be connected to either the transmitter connector or
receiver connector.
Principle of the Probe - Zero Function
Because there is a distance between the coupling surface and the
transmitter element of the transducer, the input position of the coupling
surface and the position of the transmitter element does not match.
Therefore, an error of the delay time will occur. If the "probe
-
zero
function" is not performed correctly, an error to the thickness
measurement will occur. If the "probe
-
zero function" is performed
correctly, the constant error is eliminated and the correct thickness
value will be obtained automatically.
