MTS Series 793 - Manual (Page 166)

MTS Series 793 Tuning and Calibration
Force Sensor Calibration
Calibration Procedures 166
Note If the actuator response is sluggish and/or the signal value does not
match the command, you will need to adjust the tuning of this control
mode. Increase the proportional gain (P Gain on the Tuning menu) to
correct sluggish actuator movement. Increase the reset integration value
(I Gain) to help the feedback match the command.
At this point, unless the conditioner is already in calibration, the tensile
force applied to the force transducer will not equal your commanded value.
You will adjust gain in the next step so that the actual tensile force (as
measured by the load standard) and your commanded tensile force match.
Example: Suppose your actuator has a 100% tensile force rating of -10 kN.
In this step you would apply -8 kN of command, and even though the station
signals would read -8 kN of feedback, the force standard may only read -4
kN. This shows the conditioner/sensor pair are out of calibration.
4. Adjust Post-amp Gain on the Calibration submenu or tab to increase the
tensile force reading on the load standard until it equals your tensile force
command.
5. If applicable, repeat steps 2 through 4 for all ranges.
Example: Suppose you have an actuator with a full-scale capacity of ±10 kN
and ranges of ±10 kN, ±5 kN, ±2 kN, and ±1 kN. In this case you would
repeat this process and calibrate tension at 80% of each range (-8 kN, -4 kN,
-1.6 kN, and -0.8 kN).
Note Some systems do not provide or require multiple ranges, such as those
using full-range conditioners (e.g., Model 493.25 DUC module). In this
case, only one range is used (typically 100%).
Calibrate compression
Note This procedure assumes a positive command extends the actuator and a
negative command retracts the actuator. If not, use the opposite polarity
for any values given.
1. Exercise the force sensor.
Standalone FlexTest SE Controllers: After enabling the front panel Dial,
adjust the Setpoint to cycle the load standard readout between zero and full
tension three times. This removes sensor hysteresis. Select Status >
Setpoint
Automated Controllers: Use the Manual Cmd slider on the Manual
Command window to cycle the load standard readout between zero and full
tension three times. This removes sensor hysteresis.
Example: When calibrating a ±10 kN range, exercise the load standard
between 0 and 10 kN.