Checkline MX-5 - Manual (Page 17)

MX-5 Ultrasonic Thickness Gauge
13
Probe Zero
Setting the Zero Point of the MX-5 is important for the same reason that
setting the zero on a mechanical micrometer is important. If the gauge is
not "zeroed" correctly, all of the measurements the gauge makes will be in
error by some fixed number. When the MX-5 is "zeroed", this fixed error
value is measured and automatically corrected for in all subsequent
measurements. The MX-5 may be "zeroed" by performing the following
procedure:
Performing a Probe-Zero
1) Make sure the M X-5 is on.
2) Plug the transducer into the MX-5. Make sure that the connectors
are fully engaged. Check that the wearface of the transducer is
clean and free of any debris.
3) The metal probe-disc is on the top end of the MX-5. Apply a single
droplet of ultrasonic couplant to the face of this disc.
4) Press the transducer against the probe-disc, making sure that the
transducer sits flat against the surface. The display should show
some thickness value, and the Stability Indicator should have
nearly all its bars illuminated.
5) While the transducer is firmly coupled to the probe-disc, press the
PRB-0 key on the keypad. The MX-5 will display "Prb0" while it is
calculating its zero point
6) Remove the transducer from the probe-disc.