The LHO X1 SEI test stand had some unusual parameters this morning. I was not able to isolate the table with older Robust Control filters, even with just putting a 0.1 gain on the controller.  I noticed the un-filtered geophone channels nearly saturating.  To be safe, I rebooted the frontend code, but the problem remained. 

I then checked the damping loops - they were engaged.  However, the gains on the outputs were set to 1.  I thought this was the nominal value until I tried to un-damp, then re-damp the table - no success.  The actuators saturated immediately, tripping the watchdog.  So, I then tried a negative gain and ramping from -0.1 to -1 - success.  I had forgotten the gains on the Damping loop outputs were negative -1, while all other loops have positive gains.

After this, control loops were still unstable, tripping the Displacement sensors.  I noticed the Blend filters were off, and then after enabling, the robust control filters isolated the table.

I am not aware as to how (or why) the values were changed in the medm, but the Damping outputs have been at +1 since Oct 21. The watchdog was on the brink of tripping with the +1 gain.  They seem stable now with the negative gain - geophone channels are at safe levels and isolation is on.