[Temperature sensor]

Added new temp EPICs channels to database file (/cvs/cds/caltech/target/c1pem1/tempsensor/C1PEMaux.db)

Added new temp EPICs channels to slow channels ini file (/opt/rtcds/caltech/c1/chans/daq/C0EDCU.ini)

[SUS medm screen]

Moved new SUS screen to location : /opt/rtcds/userapps/trunk/sus/c1/medm/templates/NEW_SUS_SCREENS

Place button on the new screen to link to the old screen and replace old screens link on sitemap.

Fixed Load Coefficient button location issue

Fixed LOCKIN flow diagram issue

Fixed watchdog labelling issue

Linked STATE WORD block to FrontEnd STATUS screen

Replaced the 2x1 pit/yaw filter screens for LOCK and DAMP fliters with 3x1 LPY filter screen

*Need some more time to figure out the OPTLEV red indicator

I mounted the particle counter over the BS chamber attached to the cable tray as seen in Attachment 1. The signal cable runs through an active 30ft cable to the 1x2 rack. the wire is labeled and runs properly through the cable tray. The particle counter is plugged in at the power strip attached near the cable tray. The power cord is also labeled. 

I restarted the particle counter service in the c1psl computer in the /etc/systemd/system/ folder using the commands

I cannged the usb hub assigned in the service file to ttyUSB0 which is what we saw the computer had named it.

Checking the channels from this elog show the same particle count as when testing with the buttons and checking the screen. It seems that the channels had been down but are now restarted.

nice - please update the particle counter page in the 40m wiki. Its probably years out of date.

For the proposed construction in the NW corner of the CES building (near the 40m BS chamber), they did a simulated construction activity on Wednesday from 12-1.

In the attached image, you can see the effect as seen in our seismometers:

this image is calculated by the 40m summary pages codes that Tega has been shepherding back to life, luckily just in time for this test.

Since our local time PDT = UTC - 7 hours, 1900 UTC = noon local. So most of the disturbance happens from 1130-1200, presumably while they are setting up the heavy equipment. If you look in the summary pages for that day, you can also see the IM lost lock. Unclear if this was due to their work or if it was coincidence. Thoughts?

I pressed the Auto-Z(ero) button for ~ 3 seconds at ~9:55 local (pacific) time on the trillium interface on 1X5.

This nicely brought the sensing signal back to ~zero. See attachment

Some basic info:

• BS Seismometer is T240 (Trillium)
• The interface unit is at 1X5 Slot 26. D1002694
• aLIGO Trillium 240 Interface Quick Start Guide T1000742

thanks, this seems to have recentered well.

It looks like it started to act funny at 0400 UTC on 10/24, so thats 9 PM on Sunday in the 40m. What was happening then?

I implemented the BLRMS on WFS1/2_I_PIT/YAW outputs and using there value, a HEPA state can be defined. I've currently set it up to use average of 10-30 Hz noise on WFS signals low passed at 0.3 Hz. For ON threshold of 100 and OFF threshold of 50, it is working for my limited testing time. To read HEPA state, one can do caget C1:IOO_HEPA_STATE. I've turned OFF HEPA for tonight's shimmer test. This is bare bones quick attempt, people can make the screen more beautiful and add more complexity if required in future.

this is very exciting! Its the beginning of the task of reducing vast amounts of PEM data into human-useful (bite sized) info. Imagine if we had 60 Hz BLRMS on various channels - we would know exactly when ground loops were happening or disappearing.

Over the past few days I have been trying to understand the existing sensor and heater related hardware by manual inspection and combing elogs. From what I understand, I believe a lot of the hardware was built from scratch by Kira in 2017-18. She put in place the insulation, built the sensor and heater circuits and installed and interfaced everything with EPICS. This let her successfully do step response tests and also execute PID control of the temperature of the can. As suggested by Paco, I am trying to summarise my findings in this elog. This is the block diagram of the overall system.

In the lab I was able to locate two identical temperature sensor boards, one for monitoring ambient temps and another for the can temp, which has a sensor attached to the inner seismometer can. Attachment 1 shows the actual board.

The schematic for the temperature sensor can be found here. It was later clarified that she is using AD590 and not the AD592. I tested the ambient sensor board by hooking it up to an oscilloscope and heating the sensor up. It seems to work like she described, and the output voltage goes down with heat. I will later figure out interfacing it with an ADC and calibrating it if I cannot find Kira's old work related to this. The setup there also has +/-15V Sorensen's for power (I probed these and they work), a BNC for temp readout and a bunch of other wiring for the heater. This wiring comes from the nearby rack which should have the heater circuit, but I haven't yet been able to locate it because there is too much stuff.

Coming to the heater circuit - I found the schematic for it here. I am still unsure about what the power range it can operate over, but this plot seems to imply it saturates at around 55W. This circuit underwent many different iterations so I am unsure what load resistance was actually used finally and it is not clear from the elogs. It might be a pair of heaters combined in series or parallel. Additionally, this elog by Shruti from June 2018 implies that the original circuit that Kira made ended up breaking at several different points. She said there were attempts to fix it, but I cannot find any updates after that and I think her SURF ended. I don't know the current status of the heater circuit. I am not sure where it is stored.

I was hoping to utilise the old EPICS channels set up by Kira for heater control as well as sensor readout to verify if everything was still functional and initially just read out the temperature of the can and find out how much it fluctuates. I planned to later also try to replicate the PID results. But Paco explained how the Acromag system worked and told me that utilising the old channels will not be possible right now, as all the channels have been used up for more critical tasks and none of the old interfaces that Kira had set up can be used now, even if the hardware was fine. 

Also, the can temperature sensor board has a wobbly solder joint at one of the power connectors, and we cannot move it to the lab because the sensor is anchored to the inner can. There is no power indicator LED to signal if the connection is secure so its kind of unusable right now. Paco and JC told me that soldering near the X end is not possible because the fumes would harm the optics. We will look for solutions to this. One option would be to make an entirely new board and keep a mechanical connector for the sensor. 

I wanted to mention here that I have a printed circuit board design (LIGO-D1800304) for using AD590 as temperature sensors. I believe printed boards and all required components are stored on the wire shelf in the WB EE shop on a box labeled with this DCC number. This circuit is also meant to be read by Acromag, maybe it can come of some use to you. You can check out the use in CTN lab in WB near the south-east end of the table.

1.5 days of happy psl-ioo with litle bumps in C1:PSL-126MOPA_HTEMP

• Replace the cables from the board to the front panel connectors if this hasn't already been done.
  
• Replace the input opamps with 4131's. Be sure to test both positive and negative input signals.
  
• Check that all the compensation capacitors are in place and are 68 pF
  
• Make sure all the feedback loops have high frequency rolloff
  
• The ISS board reads the PDs differentially; make sure the PD sends differentially.
  
• Add a big (ie 10uF tantalum) capacitor to the PD to suppress power supply noise
  
• Add bigger power supply bypass caps to the ISS