Epson USN 52R, USN 52L manual Automatic calibration, Higher sound velocity

Operation			USN 52R/USN 52L calibration
Higher sound velocity		– Couple the probe to the thicker part of the calibration
Due to the V-path error, a higher sound velocity than		block and peak the echo.
the test material is required when calibrating, especially		– Set the flank as steeply as possible by adjusting the
with smaller thicknesses. This is typical of dual (T/R)
		gain.
probes and acts as compensation of the V-path error.
		– Set Gate a on the first echo.
Owing to the described effect there is a drop in the
		– Set the sound velocity “C” so that the correct value is
echo amplitude with smaller thicknesses which should
be carefully observed with values < 2 mm.		displayed in the measurement line at “S=...”.
A calibration block having different thicknesses must be		Automatic calibration
used for calibration. The thicknesses are to be selected
so that they include the expected measurement value.		The instrument has an automatic calibration capability
– Set PULSER in the function group PULS to DUAL.		via the function AUTO CAL. Two calibration echoes
		must be entered. The instrument then carries out a plau-
– Set RANGE according to the test task and the probe		sibility check and automatically sets the parameter.
being used..		– Set the function AUTO CAL in the second operation
– Set TOF to FLANK.		level (right function table) to ON.
– Couple the probe to the thinner part of the calibration		– Return to the first operation level with X and select
block and peak the echo.		function group S-CALwith I.
– Set the flank as steeply as possible by adjusting the gain.		The function group S-CALchanges in preparation for
– Set Gate a on the first echo.		the automatic calibration and now contains the CAL
		function (calibration) as well as the function S-REF
– Set ZERO in the function group S-CALso that the		(sound path for the reference echo).
measurement line display the correct value at
“S=...”.	Issue 05, 02/00		Krautkramer USN 52R/USN 52L
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