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6.3 Calibration
The sensors used with the SF-902S should be periodically calibrated for highest measurement accuracy.
Not all sensor channels require calibration. Some, such as thermocouples, are calibrated at the factory and
normally do not need re-calibration. Pressure transducers and analog voltages, have the calibration set in
the configuration file based on the manufacturer’s specifications.
As a rule, the source used to calibrate a sensor should be 10% more accurate than the sensor being
calibrated. For example, if a sensor has an accuracy of +/–1%, the standard used to calibrate it should
have an accuracy of +/–0.1%.
Calibrating the Sensors
NOTE:
The following procedures are performed using the WinDyn Data Acquisition and Control Software,
please refer to the software manual for additional calibration details.
Torque:
15. Power on computer system.
16. Power on dyno system.
17. Launch WinDyn application.
18. Use
System | Install | Test
Group
menu option (or
F2
key) to load your specific test
group (.tgp) file.
19. Select
SCREEN 2
to observe
Trq1
channel (2).
20. Press ‘
C
’ key on computer
keyboard.
21. Calibration dialog box should
appear on computer screen.
22. Scroll down in channel dialog and highlight ‘
Trq1
’ channel.
23. Mount cal arm and weight pallet to absorber.
24. Click ‘
ZERO
’ button.
25. Hang cal weights on weight pallet.
26. Observe ‘
Current value = ????
’ in Calibrate dialog box.
27. Click ‘
Calibrate
’ button.
28. Enter computed torque value of hanging weights (
Weight x effective length of arm
) in calibrate dialog
box. Click
OK
. The SF-PM system uses a 2 foot arm. The SF-902s and SF-BW use a 3 foot arm.
29. Remove weights and calibration arm
6.0 Maintenance
