Reports until 16:46, Monday 29 October 2012
H1 SEI
hugo.paris@LIGO.ORG - posted 16:46, Monday 29 October 2012 (4543)
HAM3-ISI - Commissioning Work

Dave Barker and I checked the status of HAM3-ISI's test points this morning. We noticed they were overloaded. Dave restarted H1-DAQ and they came back to normal. It seems like H1-DAQ was not restarted as it should have been after the model changes of last week.

Spectra measured on HAM3-ISI make sense again. I tried most combinations of ISO/blend filters on HAM3-ISI today. I attached a sum-up plot of HAM3-ISI isolation performance in the following configurations:
1- No control
2- Damping only
3- Damping + "old" blend* 250mHz     + "old" ISO level 2
4- Damping + "newer" blend** 250mHz  + "old" ISO level 2       
5- Damping + "newer" blend** 250mHz  + LLO HAM5 ISO level 2

ISO=Isolation filters
*: old blend filters - SVN revision 6036
**: newer blend filters - SVN revision 6187

 
The results are compared to the aLigo requirement curve strored in the Seismic SVN in /Common/MatlabTools/HAM_req_for_dtt.txt. 
Before plotting this requirement curve, I multiplied its amplitude by 10^9, to turn it into nm. 
 
The configuration: Damping + "newer" blend** 250mHz  + "old" ISO level 2 is currently running on HAM3-ISI.        
 
The spectra for the other configurations tested (level 1 isolation loops performance, and performance of level 2 loops with with blend frequency at 900mHz, 750mHz and 500mHz) are available in DTT files.
 
Non-image files attached to this report
HAM3_ISI__Isolation_Performance_2012_10_29__.pdf