40m QIL Cryo_Lab CTN SUS_Lab TCS_Lab OMC_Lab CRIME_Lab FEA ENG_Labs OptContFac Mariner WBEEShop
  40m Log  Not logged in ELOG logo
Entry  Thu Sep 22 01:45:41 2011, Keiko, Update, LSC, Locking status update PRCL-OLT.pdfMICH-OLT.pdf
    Reply  Thu Sep 22 04:49:14 2011, Anamaria, Update, LSC, Locking status update - Some Scripts, No Louck 
    Reply  Thu Sep 22 11:50:37 2011, Koji, Update, LSC, Locking status update 
Message ID: 5516     Entry time: Thu Sep 22 11:50:37 2011     In reply to: 5512
Author: Koji 
Type: Update 
Category: LSC 
Subject: Locking status update 

Both loops basically have no phase margins. i.e. unstable. How can you lock PRMI with these servos?


The following rough swept sine plots are the OLTs for MICH and PRCL. The gain setting was -10 and 0.5 for MICH and PRCL, respectively. Integrators were off. Looking at the measured plots, MICH has about 300 Hz UGF, when the gain is -20, and PRCL has about 300 HZ UGF, too, when the gain is 0.8.


ELOG V3.1.3-