The following report has been submitted to the On-call interface.
On-call events -> Interferometer Sensing & Control
Title: Locking troubles
Author(s): mantovani
| Called at: 00:45, 21-11-2024, by: Gherardini |
| Remote intervention: Started: 00:45, 21-11-2024; Ended: 02:15, 21-11-2024 |
| On-site intervention: Started: ; Ended: |
| Status: Action pending |
| Operator when issue resolved: Gherardini |
Details:
I ve been called since the ITF was unlocking at CARM null.
The reason was that frequent "kicks" were visible on the powers, see figure 1, making the fringe to exceed the allowed value and unlocking the system. No loop oscillations (no margin to cure it with ISC).
We manage to make the ITF to survive CARM null by misaligning the SR ty (in the direction toward the LN3 wp) of 1urad.
To be noticed that the violins were still quite high
We made few trials but we failed during the lock of OMC.
Fabio has continued to try and after a while he managed to lock but a huge noise is still present in the region 20Hz -200Hz. To be understood, may be related to suspensions.
* Note that any files attached to this report are available in the On-call interface.
