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AdV-COM (AdV commissioning (1st part) )
Boschi, Ruggi, Trozzo, majorana - 13:15 Friday 24 March 2017 (37022) Print this report
TASK LN1_(A)
Morning shift 23/March
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We dealt with two main issues:
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I) Lock acquisition using HP board with input and locked operation in DF.
II) Lock Swap from INPUT mirror actuation to END mirror on the West arm

activity I) had been preliminary tested successfully before the shift as the lock was more stable using 56MHz signal on March 22nd.
and re-tested during the shift as the stable locking operation was recovered (OK).

activity II) implied recabling at NE site by Valerio, who also prepared a new, suitable configuration of DSP control cards at NE.
The Global Control signals are still delivered to the Mirror control card, which in turn passes mirror control to the LN control card meant
to actuate through the new board (with shaping). Now there are two boards running at 40 kHz (these two boards are both running at 40kHz)

The marionette reallocation was retuned and is kept at the level of NE payload: the swap INPUT=>END is related only to mirror level signals.
Paolo tested the system and it works. Then we kept the strategy in-line. (OK)
At the moment the acquisition is done by acting on the INPUT of N-ARM and on the END of W-ARM, providing both HP actuation.

NEXT SUSP SHIFT:
- re-checking mirror actuation digitalization to allow WI lock acquisition
- retuning the logic on the N-ARM and showing Lock acquisition with both INPUT
- aligning both DSP control cards of W-ARM to what done on NE and in parallel recabling WE mirror control cabling accordingly.

Other activity PR TY:
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Tried to remove the problem related to TY marionette actuation. Angular disturbance injected by the standard yaw marionette control (30 mHz)
affecting the sideband. ON March 22nd evening the main OpLev was redirected in order to remove a diffusive spot that could
apparently produce the problem. The problem remained and it was necessary to pass to the transversal OpLev, also producing an usable yaw signal
for controlling the payload.
Then at the end of the shift the sensor of this secondary lever (the transversal one) was reset to the zero (in order to exploit low noise sensing)
and its position with respect to the focal plane of the OpLev lens was checked to be of the order of
1% (it can be slightly improved but we'll do it only later if microseism shows-up).
We left in line for the yaw control the signal called Sc_PR_PSDt_X.

NEXT:
- we have to investigate the reason of PSDm OpLev
- check TY noise in DF (probably already doable).
Comments to this report:
ruggi - 16:49 Friday 24 March 2017 (37025) Print this report

Plot of transition to low noise.

- first step: marionette reallocation. the low frenquency part of NI correction is suppressed.

- second step: the correction is moved from NI high power board to NE low noise board (amplified by a factor of 8 and a high pass filter, zero @ 4.65 Hz, pole @ 105.5 Hz)

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