Waygate Technologies Krautkramer USM 100, Руководство по эксплуатации, Страница: 173 / 330

DAC 5 Operation
Krautkrämer USM 100 Rev. 9 (09/2023) 173
5.21 DAC
You can evaluate reflector echoes by means of the dis-
tance-amplitude correction (DAC).
After selecting DAC in the function Eval Mode in (see
page 159) the function group Evaluation provides you
with all the functions needed for the echo height com-
parison between a reflector echo and a reference echo.
Due to the angle of beam spread and the sound attenu-
ation in the material, the echo height of equally sized re-
flectors depends on the distance to the probe.
A distance-amplitude correction curve, recorded using
defined reference reflectors, is a graphical representa-
tion of these influencing factors.
If you use a reference block having artificial flaws to re-
cord a DAC curve, you can use this echo amplitude for
the evaluation of a flaw without any further corrections.
The reference block should be made of the same mate-
rial as the test object.
The time-corrected gain TCG increases the gain in dis-
tance sensitive mode so that all reference echoes reach
80 % screen height. The amplitude evaluation of echo
indications is made in relation to the first reference echo.
DAC settings
– In the A-scan tap on the Evaluation icon to display
the function group.
– In the function Eval Mode select DAC .
– Set all parameters in this function group (see from
page 158).