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Entry  Mon Sep 30 23:56:19 2013, manasa, Update, Green Locking, ALS autolocker flowchart ALSautolocker.png
    Reply  Tue Oct 1 09:51:10 2013, rana, Update, Green Locking, ALS autolocker flowchart 
    Reply  Thu Oct 3 10:29:03 2013, masayuki, Update, Green Locking, New ALS autolocker flowchart flowchart.pdf
Message ID: 9197     Entry time: Thu Oct 3 10:29:03 2013     In reply to: 9178
Author: masayuki 
Type: Update 
Category: Green Locking 
Subject: New ALS autolocker flowchart 


 [Manasa, Masayuki]

We made a new flowchart of ALS autolocker. We added the additional step to find the beat note frequency. We have to find a way to read the PSL temperature. By reading the PSL temperature we can decide the sweep range for the end green laser temperature with the curve which measured in previous measurement (in this entry)

We have three thresholds of error signal. One is the threshold for checking the arms are stabilized or not. It should be some hundreds count. Another threshold is to check that the suspensions are not kicked. This should be some thousands counts (in flow chart, it is 2K counts). The other is to check the optimal servo gain. If the servo gain is too high, the UGF is also too high and we will not have enough gain margin. The error signal start to oscillate at the UGF. We will check this oscillation and find the optimal gain. In flow chart this threshold is 1K counts.

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