13
en
Measure and Record the Ultrasonic Length, Velocity and Temperature Coefficient
You must measure these values and save the length value in the group previously created and make a
record of the values of velocity and temperature.
1.
Select MENU/CAL/ZERO MODE
2.
Use LEFT and RIGHT to adjust the ZERO MODE to FIXED
3.
Select Bolt Material Type as detailed above
4.
Make a note of the values for the VELOCITY and TEMPERATURE COEFFICIENT displayed next to
their respective sub menu items
5.
Navigate to MENU/GEOM/QUANTITY
6.
Use LEFT and RIGHT to adjust this to ELONG
7.
Set the value of ALEN/APPROX LEN (length of fastener in selected units) and conduct an AUTO SET
- see section “Auto Set” on page 29
8.
Record the Ultrasonic Length of the bolt along with the velocity and temperature coefficient. These
could also be scribed on the bolt for future zero verification
9.
Store ultrasonic length value in the group previously created (see “Quick Start” on page 3).
Perform and Save the First System Zero Verification
The next two sections outline two alternative the procedures for performing a system zero calibration by:
•
Calculating a zero value.
•
Adjusting the temperature value to match the existing System Zero value.
When to use the check zero feature:
The only time the Calc Zero feature should be used is when a different gauge, transducer, or transducer
cable is being used, other than the one initially used to obtain the system zero data for the probe zero
calibration bolt. In this case, calculating the system zero value forces the new hardware to match with the
original. If the hardware has not changed, the user should not use this function. If the hardware has not
changed, only the temperature value should be adjusted to match the existing zero values.
Performing a Probe Zero Calibration
1.
Select MENU/CAL/ZERO OPTION
2.
Use LEFT and RIGHT to adjust ZERO MODE value to ONE POINT
3.
Select MEASURE ZERO and press ENTER The ONE POINT ZERO Edit Box is displayed
4.
Highlight PHYSICAL LEN, press ENTER and adjust to match the ultrasonic length that was
determined in the previous section. This will be considered to be the actual physical length from this
point forward. Reminder: This value was stored in the first column of the System Zero group.
5.
Press OK to set the value and return to the ONE POINT ZERO Edit Box.
6.
Select VELOCITY and adjust to match the velocity of the bolt determined in the previous section.
Press OK to confirm
7.
Adjust the TEMP COEFF to match the value previously determined.
8.
Return to the ONE POINT ZERO edit box
9.
Select ULTRASONIC LEN and press ENTER, the value currently being measured is displayed
10. Scroll to CALC ZERO, press OK to set the value and return to the menu.
11. Press MEAS to return to the measurement screen
This completes the Probe Zero Calibration. If the zero value is incorrect and the hardware has not been
changed this is typically because the temperature of the bolt has changed. In this case, do not adjust the
zero value, but instead adjust the temperature value. This is also a good way to monitor temperature
changes in the bolt. The procedures below demonstrate how to adjust the temperature to match the zero
value.
.
Adjusting the temperature value
1.
Open the group in which you previously stored the system zero data - see “Opening an Existing Data
Logger Group File” on page 32.
2.
Press MEAS to return to the measurement screen.
3.
Press MEAS again and then highlight LOC in the hot menu.
