MTS Series 793 - Manual (Page 69)

How to Adjust Dither
MTS Series 793 Tuning and Calibration Tuning Procedures 69
8. Increase Dither Amplitude until the feedback is smooth.
Standalone FlexTest SE Controllers:
Select Setup > Output > Dither Amplitude
Automated Controllers:
A. In the Station Manager window’s Display menu, select Station
Setup.
B. In the Station Setup window navigation pane’s Channels, locate and
select the channel whose servovalve dither you want to adjust.
C. In the Station Setup window, click .
Three-stage valves: In the Drive panel, click the Valve tab.
Method 2:
1. Select an access level of Tuning.
2. Remove any specimen.
3. Apply hydraulic pressure to the station.
4. Increase Dither Amplitude until you can hear the dither and then decrease
Dither Amplitude until the noise goes away.
Dither Frequency
adjustment
In addition to Dither Amplitude, your Controller is equipped with a Dither
Frequency control.
The default dither frequency is 528 Hz, which is effective for most applications,
and should not require adjustment. However, if the dither frequency begins to
resonate with test frequencies, adjustment may be necessary.