sheila.dwyer@LIGO.ORG - posted 15:52, Friday 25 January 2013 (5273)
IMC WFS whitening slow controls
The slow controls are working now for the IMC WFS whitening filters.
The slow controls are working now for the IMC WFS whitening filters.
Kyle Removed bellows tie-rods from spool connecting BSC9 to BSC5 -> Started pumping X-end -> Noticed that BSC5 gauge pair was missing and a that the filter connection installed for the X-mid to X-end move of BSC5 was still connected to the gauge pair port -> Stopped pumping X-end -> Vented X-end -> Removed filter connection and installed conflat blank -> Restarted pumping of X-end 1530 hrs. local -> Valved-out pump from X-end -> will resume pumping on Monday (Rough pumping must be attended)
Observed a delayed signal response initially this morning when retesting the NE bellows -> Pumped annulus volume and applied instrument air to external leak test ports closest to NE bellows -> Retested -> OK HAM6 bellows pass leak testing.
_ clean room work in the LVEA _ ITMY work aligning with IAS and then OSEM work to recover centering _ IO transfer functions and additions to IOT2L and the PSL _ HAM2 East got a camera mounted on a viewport last night _ MC locking needed help after the reboot and installation of the LLO MC2 model yesterday _ Cables pulled around HAM1/2 _ Photon Calib. hardware brought into the LVEA _ Dust monitors - the MEDM means nothing about where these dust monitors are, just FYI Still coming today: ___ DAC reboot
I've installed the liquid cooled dump 2 of 2 (for the IO) on the PSL table near the PMC output. I did not connect the water lines since the laser was in use at the time although it doesn't appear that loop has flow meters installed. The dump is not in a beam path at the moment since the power meter is still in use in its intended location.
Filiberto and I ran the PZT controller cables through the rack feed-through to the PSL. I did not connect them to the controller since they weren't terminated at the time. I've zip tied them to a bolt on the table surface near the controller.
Arnaud P and Mark B. Starting a round of tfs after the alignement of suspensions
All of the components have been installed on IOT 2 with their final optics except for the Trans Mon PD. Some small deviations were made from the layout D0902284. 1) The IO_SM2T_GIGE2 camera was moved to the left of IO_SM2T_GIGE1 to avoid the periscope base similar to what was done at LLO. 2) IO_PRMR_BS1 and IO_PRMR_BS2 were turned to send dump the beam toward the chamber in order to use right handed mirror mounts. There were some issues installing the patch panel blanks, not all of which fit properly. The mounting holes for them are of very close fit and probably need to be drilled slightly larger. I have left the screws out in these places. Also on the left side, one of the large panels was too wide to fit and will need to be machined down slightly. At this point the table is considered clean space and access requires proper garb. Also the HEPI fan must be kept running. I've marked off the cutout for the beam penetration and arranged with Kiwamu to have that machined. The opening will need to be covered with plastic as with the other tables when the panel is removed for machining. I've also arranged with apollo to have the aluminum spacers installed to lift the table to the "LHO" height.
Took spectra of the IMC length control signal with different control configurations for HAM2-ISI and HAM3-ISI. In comparision to measurements with damping only, most improvement in the 0.5Hz-3Hz range were seen with Level 2 isolation and 100mHz Sensor Blend on translational DOF, and 250mHz Sensor Blend on rotational DOF.
Both HAM-HEPIS were locked, and control configurations (ISO level, and blend) are systematically the same for both ISIs. One should note however that level 2 controllers used here are specific to each chamber. I will try having the exact same filters on both ISIs to limit the differential motion injected later.
I haven't managed to calibrate these curves yet. I am working on it and it should come soon.
These measurements were performent yesterday, with the IMC locked using Matt's new MC2 M2-M3 cross-over. This recent modification of IMC controls allow keeping the IMC locked, even with the level of differencial motion injected at low frequency by the Lv2 ISO /w 100mHz X,Y,Z blend & 250mHz RX,RY,RZ blend configuration. The seismic isolation is then optimal, in comparision to what we obtained so far, in the 0.5Hz-3Hz range.
SImilar measurements taken on Jan 18th for comparison.
I've noticed that this was not alog-ed yet, so here it is.
1: Oscillation
Right after WFSs were powered up originally on Jan/16, WFSA segment 1 and 4 showed some crazy thing going on, which continued for 9 hours or so (first plot, the vertical line in CH2 and CH3 indicates the time of installation). This is the head the installation crews reported to be hot, so the oscillation thing was there from the start, but this may be a different problem from the death of WFSs.
2: Death of WFSB at 13:17:47 local time propagated to WFSA, then to MC REFL almost instantly
On Jan/22 at 13:17:43 local time, when WFSB was malfunctioning and outputing a bogus offset, something happened to WFSB and the output went zero-ish. (Second plot).
Four seconds later, something drastic happened that caused huge spikes to everything.
Though you might not be able to see it, first WFSA WFSB saw a spike, then 4/16 seconds later WFSB WFSA, then 2/16 seconds later MC REFL PD, in this order. Though the timing of EPICS is sort of dubious, we're not talking about 1 sample time difference here and I'm sure this order is correct.
None of WFSA segments responded to light since then, and REFL DC developed a large offset since then.
When everything was dead, CM board power was tripped also. WFSA and WFSB are connected to the same chassis, but MC REFL is connected to a different chassis, and CM board is in yet another chassis.
Though it's not on the plot, we didn't find any suspicious thing in the PSL except obvious things (e.g. FSS disturbed by MC servo which was kicked by the incident).
3: Did WFSs die when the breaker of the WFS DC interface tripped?
As I reported earlier, at some time on Jan/22 the DC WFS interface went bad (it was the power protection board) when I was measuring WFSB supply voltage, and the breaker switch was tripped. I was the only person in front of the field rack at that time.
But it's not clear if I was in the LVEA at 13:17. Combining blurry memory of me, Filiberto and Kiwamu, plus an incomplete record of the card access system (it didn't register my swiping out when I went out of LVEA when somebody else opened the door to go out or come in, or I didn't bother to swipe out and just went after somebody else), it's not impossible that the breaker tripped when WFSs died.
Mark B. Preparing to do a set of Matlab TFs on IM1 to test out new provisions in the code for HAUX. The main focus at this point is for the script to run at all, so Filiberto's cabling work and other minor disturbances are not a problem.
Mark B. Done for now - I debugged all the preamble and the script now gets as far as applying the excitations. I'll try a full run tonight when the IO team is done for the day.
Attached are plots of dust counts > .3 microns and > .5 microns in particles per cubic foot requested from 5 PM Jan. 23 to 5 PM Jan. 24. Also attached are plots of the modes to show when they were running/acquiring data. Dust monitor 10 in the H1 PSL enclosure is still indicating a calibration failure. The data was taken from h1nds1. No data output errors were returned, but the plots were generated. 5100 seconds worth of data was unavailable on this server 1306.0 minutes of trend displayed
Many thanks to Joe and Keith at LLO for building a new l1susmc2 model. The main changes are:
l1susmc2 links to the MC_MASTER model.
In MC_MASTER, the links to the SIXOSEM_T_STAGE_MASTER and FOURSTAGE_MASTER are removed, these parts are now incorporated into MC_MASTER and modified for MC2.
The MC_MASTER has three outputs for the X_M1,2,3 stages which are filtered and summed by the IMC block.
We updated sus/common/models and sus/l1/models, then transitioned l1susmc2 to h1susmc2.
The original H1SUSMC2.txt filter file was kept, with the three IMC filter modules appended from the LLO L1SUSMC2.txt file.
After the h1susmc2 restart, I burt restored back to 4pm this afternoon.
The DAQ was restarted as part of the install. Some mx_streamers needed restarting on other frontends.
Giacomo, Matt, Lisa In the last few days we tried to use the Laser Head Calibrator (4mW @ 980nm, D1201258, S/N S1300150) to check the RF chain of the IMC LSC RFPD. The idea is to use this type of LHC for all the ISC RF sensors to make sure that the signal chain from the sensor to the ADC works properly. Before using the LHC on the LSC RFPD, we used it on an 1811 to calibrate the RF input of the laser head. We got about 13 mW/V. We then used the LHC on the IMC LSC RFPD (24.078 MHz) installed on IOT2. We drove its RF input at 24.078473 MHz (100 Hz off from the IMC modulation frequency) to produce a 100 Hz sine in the I and Q demodulated channels. However, the amplitude of the sine was much smaller than what we expected (something like a factor of 50), given the RF input calibration factor and the diode responsivity measured with the DC response. Since this measurement was supposed to be straightforward, we took this defeat personally and decided to bring the LHC back to the electronics shop and do more testing. After using it on another 1811, a spare LSC RFPD and one of the BBPDs, we finally realized what the problem was. One end of the R1 50 Ohm resistor which couples the RF into the laser head was not soldered .. so the level of RF which we were sending in was correct only if the cable was bent in such a way to make the connection...soldering that end helped :-) So, for a spare LSC RFPD for 24.078 MHz (S/N S1203398) tested in the lab we get: V_DC = 4 [mW] x Resp [A/W] x 100 [V/A] = 180 mV ==> Resp [A/W] = 0.45 (this also takes into account the overlap factor with the diode) Vout_RF/Vin_RF @ 24.078 = 8.5 dB => with V/A = 476 and the Resp A/W = 0.45, this is consistent with the 13 mW/V calibration of the LHC RF input. The message We can now test again the laser calibrator on the IMC LSC RFPD, and hopefully we will get something that makes sense.
Mark B and Arnaud P. We took DTT transfer functions on M0 and R0 of ITMy: ^/trunk/QUAD/ITMY/SAGR0/Data/2013-01-24_1300_H1SUSITMY_M0_*_WhiteNoise.xml ^/trunk/QUAD/ITMY/SAGR0/Data/2013-01-24_1300_H1SUSITMY_R0_*_WhiteNoise.xml Main chain looks very good. Reaction chain is a bit messy but very similar to previous measurements from when it was H2 ITMy. Next step is to work with IAS to set the pitch of the main chain.