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5. Press ENTER to display the Digits Edit Box.
6. Press OK to set the coating velocity and return to the measurement screen, or ESC to cancel.
Note: CHECK YOUR CALIBRATION. Place the transducer back on both calibration points. If the
coating thickness readings match the known thickness values of each sample calibration has been
successful and you are now ready to take measurements. If the thickness is not correct, repeat the
steps above.
8 MEASUREMENT - TAKING READINGS
Disclaimer: Inherent in ultrasonic thickness measurement is the possibility that the instrument will
use the second rather than the first echo from the back surface of the material being measured. This
may result in a thickness reading that is TWICE what it should be.
Responsibility for proper use of the instrument and recognition of this phenomenon rests solely with
the user of the instrument.
Other errors may occur from measuring coated materials where the coating is insufficiently bonded
to the material surface. Irregular and inaccurate readings may result. Again, the user is responsible
for proper use and interpretation of the measurements acquired.
8.1 BEFORE YOU START
•
Prepare the surface - see "Condition and Preparation of Surfaces" on page 47.
•
Ensure the correct transducer is selected and set in the gauge - see "Transducer - Setting
Type Of" on page 16.
•
Select the correct measurement mode (P-E, PECT, PETP, E-E, E-EV, CT) - see
"Measurement - Modes" on page 10.
•
Set the zero point of the transducer - see:
•
"Transducer - Zeroing" on page 12 and
•
"Transducer - Zeroing for Coating Only Measurements" on page 13.
•
Calibrate the gauge - see:
•
"Calibrating - for a Material" on page 14 and
•
"Calibrating - for a Coating" on page 15.
•
Choose the measurement view (DIGITS, RF or RECT, or B-SCAN) - see "The Measurement
Screen" on page 6.
8.2 PROCEDURE
1. Apply couplant
For the gauge to work correctly there must be no air gap between the transducer and the
surface of the material to be measured. This is achieved using a couplant.
Before the transducer is placed on the surface, put a small amount of couplant supplied with
the gauge on the surface of the material. Typically a single drop is sufficient.
2. Place transducer onto the surface of the material to be measured
Place transducer onto the surface of the material to be measured
Press the transducer wearface into the couplant. Only moderate pressure is necessary to
keep the transducer stationary and the wearface seated flat against the surface of the
material.
3. Read display
If six or seven bars of the stability indicator are showing, the display will be reading the correct
thickness of the material directly beneath the transducer.
If the stability indicator has fewer than five bars showing, or the numbers on the display seem
erratic, check to make sure that there is an adequate film of couplant beneath the transducer,
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