GE DMS Go+ Operating Manual page 107

Carrying out the calibration
– When the message Remove probe from Cal Std. is
displayed on the screen, you can uncouple the probe.
The 1-point calibration is finished, the instrument is
calibrated to the zero and to the sound velocity in the
calibration block. The new sound velocity is displayed
at the top edge of the display screen.
2-point calibration
The 2-point calibration is recommended especially
when using dual-element probes in order to compen-
sate for the V-path errors typical of these probes and li-
able to affect the measuring accuracy.
A stepped calibration block with 2 different thicknesses
is required for the 2-point calibration. The wall thick-
nesses must be selected in such a way that they cover
the expected measurement readings.
– In the function group PROBE&CAL, select the func-
tion THK CAL.
– Choose the option 2-PT.
– In the function group PROBE&CAL, select the func-
tion CALIBRATION.
DMS Go+
– Press one of the left or right arrow keys in order to
start the calibration. The message Couple to Low
Cal Std. (displayed below) or press ENTER to
change low cal. block thickness. is displayed on
the screen.
– If the wall thickness displayed on the screen is not
identical with the low-calibration thickness calibration
block, press the function key 2 (function ENTER).
– Select the digits that you wish to change using the
left and right arrow keys, and change the value using
the up and down arrow keys.
– Press the function key 2 (function DONE) in order to
close the process of changing the thickness value.
– Apply some couplant to the low-calibration thickness
calibration block and couple the probe. After finishing
the measurement, the message Remove probe
from Cal Std. is displayed on the screen.
– Uncouple the probe. The message Couple to High
Cal Std. (displayed below) or press ENTER to
change high cal. block thickness. is displayed on
the screen.
Edition 4 (05/2014)
5 Operation
5-29