[Tomaru, Uchiyama, Washimi, Yokozawa]
When we knocked the BS frame for testing the hammering test (very gently). the BS tripped.
The software watch dogs worked and DAC output for the IP and GAS control were saturated.
So I moved safe state. Then we can move the aligned state smoothly.
After recovering the inteferometer, we touched the BS frame(very very very gently), we found the peak around 20-30Hz.
15.9Hz, 16.8Hz, 26.6Hz, 32.3 Jz, 37.8Hz
As I said many times, simply never touch those white structures (outer frames) of the Type-B suspensions without undrstanding what are you doing. Just dangerous. Too innocent. No "very very very". Just stop it for god's sake.
Air touching the BS frame a lot.
Some cable is touching.
How to investigate the vibration of the BS frame is under the sensitivity curve? Is acoustic injection OK?
I took a loot to the event upon Yokozawa-san's request.
Date and time of plot below: Sunday 2020-03-15 from 4:30:00 to 5:30:00 UTC (from 13:30 to 14:30 JST).
Besides showing the data that confirms the IP tripped my only comment is that I don't remember the other frames to be as delicate as Yokozawa-san's description of the BS' one. This includes VIS postintallation work and PEM work, e.g. installing accelerometers in SR3 upper oplev platform, removing a heavy leaning flange from SRM frame, etc.
I need to pay attention to this situation after the observation campaign and before we open the chamber for VIS work. I wonder what this may sugget about the assembly of the frame.
The plots show the IP actuation reaches saturation at -20,000 counts in the three coils, which is the limit set in the medm screen. Then oplev signal also goes out of range (beyond ±100 normalized displacement units).
I took a loot to the event upon Yokozawa-san's request.
In case you don't see the plot below please click here: 13659.
Date and time of plot below: Sunday 2020-03-15 from 4:30:00 to 5:30:00 UTC (from 13:30 to 14:30 JST).
Besides showing the data that confirms the IP tripped my only comment is that I don't remember the other frames to be as delicate as Yokozawa-san's description of the BS' one. This includes VIS postintallation work and PEM work, e.g. installing accelerometers in SR3 upper oplev platform, removing a heavy leaning flange from SRM frame, etc.
I need to pay attention to this situation after the observation campaign and before we open the chamber for VIS work. I wonder what this may sugget about the assembly of the frame.
The plots show the IP actuation reaches saturation at -20,000 counts in the three coils, which is the limit set in the medm screen. Then oplev signal also goes out of range (beyond ±100 normalized displacement units).
