Over the last few days, we have been occasionally been locking the ISI to the position sensors below 90mHz along the beam direction when the wind is high.

The general idea is that wind causes the ground to tilt, at low frequencies this shows up as a huge translational signal in the interial sensors, so we are better off controlling the ISI with position sensors to higher frequencies when the wind is high.  This means that we give up some isolation at the microseism, so it might not be a good idea to do this when the microseism is high.  The last few days the 0.1-0.3 Hz BLRM has been hovering around 0.4 um/sec, in this situation blending high along the beam direction when the wind is steadily above 20 mph seems to help us. 

I've attached a screen shot of the configuration that I've just switched the Y end to, this only takes two button clicks, switch the Y blend from 45 mHZ to 90 mHz, and turn off the output of the sensor correction in the Y direction. 

At X end we have been doing the same blend switching along the beam direction, but here we have the BRS, which can be used to subtract the wind induced tilt from the ground seismometers so that sensor correction can give us some benefits even durring windy times.  So the X end procedure is three clicks:  raise the X blend to 90 mHz, turn off the unocrrected X sensor correction by typing zero in the ISI_CUST_CHAMBER_STS2CART screen at the X X2 position, then turn on the corrected sensor correction by typing a 1 in the X X3 position.  Before and after screen shots attached.