At present, the PT01~04 output became stable. So this fluctuation comes from the unstability of the cryocon or wiring connection trouble due to yesterday's activity on the metal mesh? Ikeda-san and Yokozawa-kun, do you have any idea?

Actually, the fluctuation is sometimes so fast. It cannot be induced by thermal influence from the mesh area to the optical table.

On the other hand, PMC output oscillation continues.

I may not understand the situation correctly, there are possibility that the pin assignment affect something.
5 pin used in cryocon, as shown in JGWDoc14102.

 

2023.09.28Activity log
1315 Entering PSL room
1330 Pico motor driver installed, LAN cable wired
1400 Start operation test of motor driver and rebooter after AC connection
1403 Completed equipment installation
1405 Replace PMC2(M4) and begin testing
1535 Returned to original PMC2(M4)
1540 Exit from PSL room
Times are approximate.

To investigate the cause, the copi motor driver, rebooter, and network switch are all powered on but not connected to the motor, so they can be turned off by entering the PSL room.
 

Before these activities, the PSL mode changed from Observation mode to Working Mode.

After finishing these works, the PSL mode changed from Working mode to Observation mode.

After this installation or work

• some PT thermometer shows the strange change of temperature as Fig.1.
• PMC out shows strange oscillation as Fig.2. (23 minutes) 

Some stuff on the metal mesh and AC adapter might affect the PT thermometer by heat or electrical noise. Or did you put something whose heat can vary on the optical table? Or did you check a stray light was properly dumped around your touched optics? Or some activities of putting the stuff on the mech affected the connection of wiring for PT01-04?

To check the influence, it is better to remove them or check the difference before and after your work.

In addition, some monitors for PC/servers are better to be turned off.

23 min oscillation seems to vanish after reducing the IMC output (= FBL output ?) from 17W to 15.5W level.

We disconnected power supply cables of pico driver and network switch installed yesterday.
A power cable of the driver was disconnected at 10:52:23 JST.
A power cable of the network switch was disconnected at 10:53:37 JST.

Figure 1 shows the trend of temperature of PT01-06.
Left and right T cursors show 10:52:23 and 10:53:37 JST, respectively.

After the right T cursor, the temperature seems changed significantly, so the network switch might affect the cryocon outputs.
However, I'm not sure why the temperature outputs became unstable and somehow recovered yesterday.

Although the step size is so small, a strange step change in PT01-06 happened again, except for PT05.

A large data violation has happened again. The cryocon itself or its cabling seemed to be affected by something after putting instruments.

PT05-06 seems to be almost free from this phenomenon. This can be a hint.

Is there any difference of the cabling route for PT01-04 and PT05-06? Did Ushiba-kun disconnect the "LAN cable" also, in addition to the power line?

We didn't disconnect all LAN cables but disconnected LAN cable for PoE of network switch.

In the ground voltage channels, a glitch was found around 12:30 UTC on Sep.29.

However, is was not so drastic compared to other times.

KTanaka-san, Ikeda

The PMC Picomotor and other equipment installed in the PSL room during K-Log #26965 has been removed.Fig-1, Fig-2, Fig-3
After installation, PT01~04 became unstable as described in K-Log#26969.
We need to see if removal will remedy these problems.

The equipment were placed in cases and placed to back side the PSL room. Fig-4
Next time we will install the Picomotor cables from the PSL room to the back of the PSL room .

PSL Work Time
Start: JST:11:41:53 GPS Time: 1385433731
Finish: JST:12:14:52 GPS Time:1385435710

After these activities, the temps of PT01-06 are now decreasing by ~0.02 ~ 0.4C because of the removal of heat generators such us drivers. So I changed the temp setting of the #2 cooler to 23.15 from 23.05C around 21:00.

By the way, the data of PT02 and PT04 seem to become noisy. So, it is better to check the connections of the wiring for PT02. We need more time to check the data jumpings.

No signal jump was observed after these actions for 2.5 days. So some of the removed electronics could be the source of signal jumps.

By the way, this photo shows the touch of the D-sub connector with the metal meshes. It is better to cover the white shell again that seems to be violated.

Because the temps of PT01-06 seem to decrease by ~ 0.02C, I changed the #2 precision cooler temp setting from 23.15 to 23.17 on 4th Dec.

Temps seem to increase by ~0.02C, and no jumps are observed. By the way, the noise in PT02 can be 60Hz?

Fig shows the PT01-06 values and PMC/IMC output. Around yesterday evening, PT01-06 reduction (however, only 0.02C) seemed to be correlated with the reduction of the PMC/IMC output.

In addition, the noise in PT02 became smaller. The precise timing of PT02 reduction was 22:59 7th JST (13:59 7th UTC) on 7th Dec.

kTanaka-san, ikeda

Continuing from last week, we installed PMC pico motor cables in the PSL room.
From the PSL room mesh shelves to the back side of the PSL room.

It is not yet connected to a motor driver.
It will be connected at the next PMC mount replacement work.

start time: 2023/12/08 10:34:50(JST), 1386034508
End Time: 2023/12/08 11:12:03(JST), 1386036741