Dakota Ultrasonics CMX DL plus - Manual (Page 52)

Dakota Ultrasonics
48
6.2 Probe zero
The next step is to perform a probe zero. The zero function is a very important and
necessary function that must be done prior to calibration. It should be done on a
regular basis. In fact, the CMX
DL+
has been programmed to force this issue at
regular intervals during operation if it hasn’t been done. If the CMX
DL+
is not zeroed
correctly, all the measurements taken may be in error by some fixed value. When
the CMX
DL+
is using the auto zero (electronic zero), the CMX
DL+
can be in any
measurement mode. However, when the manual zero is being used, the CMX
DL+
must be in pulse-echo mode in order to perform the zero. The CMX
DL+
will also see
to it that this occurs by simply forcing the gauge into this mode when zero.
Therefore, if the CMX
DL+
is in the echo -echo measurement mode and a manual zero
is being performed, the CMX
DL+
will put the gauge into pulse-echo mode
automatically before performing the zero. While this is a very convenient feature of
the CMX
DL+
, the user should be sure to check the measurement mode following
calibration to be sure the CMX
DL+
is in the desired mode. The following steps outline
both of these techniques.
The CMX
DL+
is equipped with two zero options:
1) Off Block Zero (Automatic Probe Zero) – When this feature is enabled the
CMX
DL+
will do an electronic zero automatically, eliminating the need for a zero
disk or block.
2) On Block Zero (Manual Probe Zero) – When this feature is enabled the
transducer must be placed on the probe zero disk (battery cover located on the
top of the unit.
Both zero procedures are outlined as follows:
Performing an Auto Probe Zero (Off Block)
Coating Probe Identified Coating Probe Not Identified