Panametrics PT878GC, Instruction Manual

Page: 158 / 224

Chapter 9.
148 TransPort™ PT878GC User’s Manual
9.1.4.4 Calibrating the Thickness Gauge Transducer
To zero the transducer offsets, go to the Zero tab. Press the [

] or [

] arrow key until you reach the Zero tab and
press [ENTER] . The screen appears similar to Figure 137 below.
Figure 137: The Zero Window
1. Press the [

] arrow key to enter the window.
2. The first prompt asks you to choose between single and dual-point calibration. Use the [

] and [

] arrow keys
to move to the appropriate radio button and press [ENTER] .
Note: Panametrics Sensing recommends dual calibration. Dual-point calibration is more reliable, but it requires
two known thicknesses of the calibration material.Use single-point calibration only if you know the sound
speed in the calibration block material to a high degree of accuracy. See Appendix C for more information.
3. The next prompt asks you to enter the length of Block 1. (If you are using a Panametrics Sensing-supplied test
block, the length is printed on the block.) Press [ENTER] to open the text box.
a. Press [ENTER] to open the text box.
b. Use the numeric keys to enter the length.
c. Press [ENTER] to confirm the entry.
4. Press [ENTER] (Calibrate button) to prepare for calibration. Then apply couplant B to the block surface, and hold
the transducer against the block.
5. When you have the transducer firmly pressed against the block, press [ENTER] (Ready button) again to perform
the calibration.
6. Hold the transducer steady until the Set button appears. Press [ENTER] to store the calibration.
IMPORTANT: Be sure to hold the transducer steady until the Panametrics Sensing wait cursor disappears.
7. If you have chosen dual calibration, repeat Steps 3 through 6 above for Block 2.
8. The PT878GC asks for confirmation of the calculated and current values.
• Press the [

] arrow key to move to the Retry box and press [ENTER] to recalculate the value, or
• Press [ENTER] on “Set” to commit the calculated value.
Once you have completed calibration, the transducer should remain calibrated until the meter memory is cleared or
a dramatic shift in ambient conditions occurs.
To leave the Zero window:
Display
Thickness Gauge Measure
Cancel
OK
Graph
Velocity
Zero Material
Block 1 Length
Calculated Current
Transducer Delay,
0
0
Single
Dual Calibration
0 mm Calibrate
µs