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Entry  Mon Aug 20 11:36:44 2012, Steve, Update, SUS, ETMX is not happy 
    Reply  Mon Aug 20 13:10:31 2012, jamie, jenne, Update, SUS, ETMX is not happy 
Message ID: 7235     Entry time: Mon Aug 20 13:10:31 2012     In reply to: 7233
Author: jamie, jenne 
Type: Update 
Category: SUS 
Subject: ETMX is not happy 

Quote:

ETMX has some periodic oscillation. It's damping was found tripped this morning. 

We tracked this down to the power normalization stuff that Yoichi added over the weekend.

With a non-zero normalization factor, and a small TRX transmission, the input the XARM controller gets really big.  When XARM is then triggered, a huge impulse is sent into the SUS_ETMX_LSC input, which causes the Vio2 filter in FM0 to ring like crazy.  This probably also explains why Yoichi was seeing trouble locking the arm when the normalization is on

The solution, as Yoichi also mentions, is probably to trigger the normalization like we trigger the rest of the boost filters.

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