Detection Of Echo 1 And Echo 2; Figure 10-13 Negative And Positive Echo Detection Examples - Olympus 45MG User Manual

DMTA-10022-01EN, Rev. C, January 2015
10.8.1

Detection of Echo 1 and Echo 2

It is possible to select the detection polarity (positive or negative) for the first and
second echoes. Depending on the measurement mode and on the type of test material,
the maximum amplitude in an echo can be either a positive or negative peak. Positive
and negative polarity refer to processed echoes displayed on the waveform display
(see Figure 10-13 on page 179). To measure thicknesses with the highest accuracy, it is
important for the 45MG to detect the maximum amplitude peak in an echo.
Negative maximum peak Positive maximum peak
Negative detection of a steel-air interface Positive detection of a plastic-steel interface

Figure 10-13 Negative and positive echo detection examples

Refer to Table 12 on page 180 for assistance in selecting the appropriate detection
polarity for a given application.
Custom Setups for Single Element Transducers 179