Identifying The Velocity Reference Block - GE MFE DMS 2 Operating Manual

8. Application Notes and Optional Features
Step 4: Press
.
Step 5: Couple the probe to the coated side of the coated
calibration standard. If the displayed material thickness equals
the thickness measured from the uncoated side of the standard
(from Step 3), the coating velocity is correct. If the two thick-
ness values (from Steps 3 and 5) are not equal, continue with
Steps 6 and 7.
Step 6: Press at the same time. Then press below
the selection labeled TOP CT ZERO.
Step 7: Press below the CT. VEL (coating velocity)
selection while the probe is coupled to the coated side of the
standard and observe the material thickness value. Continue to
adjust the coating velocity until the material thickness equals
the uncoated thickness found in Step
8.4.5

Identifying the Velocity Reference Block

Your TopCOAT probe was supplied with a dedicated velocity
reference block. The block is made of copper. The block's
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3.
thickness, acoustical velocity, and serial number may have
already been entered into your instrument. To change this
information in your instrument, follow this procedure:
Step 1: Activate the Secondary Master Menu (by pressing
at the same time).
Step 2: Press
below the selection labeled TOP CT ZERO.
The command "ENTER TC VEL. REF. BLOCK
ATTRIBUTES" will appear on the display screen, along with
these three selections:
VELOC—the known velocity of the velocity reference block
(stamped on the block in inch and mm units)
SERNUM—the block's identified serial number
CT. VEL—the acoustic velocity of the test piece's coating
Step 3: Press below the VELOC selection to input the
known velocity value that's stamped on the velocity reference
block. Input the velocity value (inches or mm) that matches the
UNITS setting (see Chapter 3 to set UNITS).
DMS 2 Operating Manual