– 7 –
When the IN symbol is on, the TI-25M-MMX is
displaying a thickness value in inches. The
maximum thickness that can be displayed is
19.999 inches.
When the MM symbol is on, the TI-25M-MMX
is displaying a thickness value in millimeters. If
the displayed thickness exceeds 199.99 millime-
ters, the decimal point will shift automatically to
the right, allowing values up to 1999.9 millime-
ters to be displayed.
When the IN symbol is on, in conjunction
with the /µs symbol, the TI-25M-MMX is
displaying a sound-velocity value in inches-
per-microsecond.
When the M symbol is on, in conjunction with
the /s symbol, the TI-25M-MMX is displaying
a sound-velocity value in meters-per-second.
When the + symbol is on and blinking, this indi-
cates that the TI-25M-MMX is currently operat-
ing in echo-echo ( Thru-paint/coating ) mode.
3.6 Probe Zero Plate
When first connecting the probe supplied with the TI-25M-MMX, the user
should perform a “Probe Zero” as described in Section 4.2. The Probe Zero
Test Plate is used for this task. It is located on the top edge of the gauge as
shown in the photo below. It also serves as the battery compartment cover
Note:
The thickness of this plate is not important, and it should not be
used as a Calibration Test Plate. A precision 4-step Test Block is optionally
available for this purpose.
1.8.8.8.8
+
IN
MM/
µ
s
1.8.8.8.8
+
IN
MM
/
µ
s
1.8.8.8.8
+
IN
MM/
µ
s
1.8.8.8.8
+
IN M
M
/
µ
s
1.8.8.8.8
+
IN MM/
µ
s
– 22 –
7. Press the CAL key again and the acoustic velocity units indicator
“IN/µs” or“M/s” will be flashing showing the acoustic velocity
value that was calculated for this sample. If desired, record this
value so it can be re-entered easily in the future.
8. Press the CAL key again to exit the calibration mode and return to
the measurement mode.
Note: If the CAL key is pressed while in the calibration mode, the
TI-25M-MMX will be reset to the factory default calibration for common
steel (0.2330 IN/µs or 5920 M/s).