MTS Series 793 - Manual (Page 203)

Extensometer Calibration
MTS Series 793 Tuning and Calibration Calibration Procedures 203
4. Set the calibrator micrometer head for 80% of the negative full-scale value.
5. Note the monitored strain signal value.
6. If the signal value does not match the set value, adjust the transducer
excitation voltage to achieve an 80% value (–8 V DC). Record your final
strain signal value for the 80% output.
Note After determining an approximate excitation value, round it to convenient
value (e.g., 8.00 V DC). Use Post-amp Gain to make fine adjustments of
calibration.
Calibrate the positive
output (compression)
To calibrate the positive extensometer output:
1. Adjust the calibrator between zero and 100% of the extensometer’s full-
scale range three times. This exercises the extensometer to remove any
hysteresis.
Note Before clicking Auto Zero, ensure that any offsets due to Auto Offset
and Manual Offset actions are eliminated
2. Use Auto Zero to zero transducer output.
Standalone FlexTest SE Controllers: Select Setup > Strain > Offset/Zero
> <<Auto Zero>>
Automated Controllers: Click Auto Zero on the Calibration tab to set
transducer’s amplified output to 0.000 V DC.
3. Set the calibrator micrometer to 80% of the positive full scale value.
4. Note the monitored strain signal value.
5. Adjust Delta K to achieve an 80% value (+8 V DC).
Note The Delta K value can be adjusted above or below 1.000. This means it
will correct for an error above or below 8 volts.
Compare recorded
data points to
calibration sheet
Your sensor should include a calibration data sheet that shows the data point
tolerance.
1. Record the negative and positive outputs values at the 20%, 40%, 60%, and
100% data points.
2. Compare your recorded output values to the calibration data sheet that
accompanied your sensor.
3. Make sure your current values fall within the permissible variation.