Checkline MX-5 - Manual (Page 8)

Dakota Ultrasonics
4
The PRB-0 key is used to "zero" the MX-5 in much the same way that a
mechanical micrometer is zeroed. If the gauge is not zeroed correctly, all
of the measurements that the gauge makes may be in error by some fixed
value. Refer to page 13 for an explanation of this important procedure.
The CAL key is used to enter and exit the MX-5's calibration mode.
This mode is used to adjust the sound-velocity value that the M X-5 will use
when calculating thickness. The gauge will either calculate the sound-
velocity from a sample of the material being measured, or allow a known
velocity value to be entered directly. Refer to page 14 for an explanation of
the two CAL functions available.
The IN/MM key is used to switch back and forth between English and
metric units. This key may be used at any time, whether the gauge is
displaying a thickness (IN or MM) or a velocity value (IN/
µs or M/s).