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Reports until 12:24, Wednesday 21 January 2015
H1 SEI
hugh.radkins@LIGO.ORG - posted 12:24, Wednesday 21 January 2015 (16183)
EndX ETMX BSC9 HEPI Guardian restarted wp 5019

Using the Guardian manager, brought down the entire ETMX SEI after capturing the current held position for HEPI.  The Guardian code has been changed to restore all 8 dofs on HEPI to reduce or nearly eliminate alignment changes from lock to lock.  Before HEPI only restored the RZ and Pitch at the ETMs.

The Guardian smoothly brought the system down with no trips.  Restarted the Guardian code and then went directly to fully isolated first time.  No problems with the idea then.  I'll step this through all the platforms as commissioners allow.

Of note, none of the DOFs on the BSC-ISI are restored like this (As opposed to the HAM-ISI where all dofs are restored.)  So, I attach a plot showing the before and after of this morning's restart.  The op-levs are shown and the HEPI RZ.  Additionally, all the rotational dofs of the two ETMX ISI stagesare show to reveal at least one lock to lock alignment change on the ISI.  All the SEI channels are in nano units, Oplevs are urads I believe.  The Stage1pitch is worst at 600nrad tilt, all others are much smaller.

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