Sawada, Uchiyama
We observed a sudden surge in vacuum pressure at Y-15, as depicted in Figure 1. This increase occurred at 8:29 AM on October 2nd. The vacuum pressure rose from 0.9E-7Pa to 1.3E-6Pa before stabilizing at 1.0E-6Pa by 9:30 AM.
Following this, we conducted a check of the TMPs in Yarm and discovered that the TMP at Y-10 had unexpectedly ceased functioning. The controller of the TMP displayed “No response” (Fig. 2). Additionally, the failure indicator on the main body of the TMP was illuminated (Fig. 3), and the interlock system also issued an alert (Fig. 4).
On the positive side, the dry pump and the chiller for the TMP continued to operate normally.
We closed the GV at the TMP head and toggled the TMP on and off. The “No response” message disappeared. Then, we reset the interlock system and restarted the TMP. Finally, the TMP returned to normal. Since we should investigate the cause of this issue, we did not open the GV.
We will retrieve the information stored in the TMP to gain a better understanding of the situation.
[Kimura, Yasui and Uchiyama ]
On the afternoon of Oct. 5, when we checked the fault history using the TMP’s external controller, the attached error log was displayed.
Based on a comparison between the internal clock and my watch, we estimate that this error occurred around 8:30 a.m. on Oct. 2.
On Oct. 6, we plan to extract the operation history stored in the TMP and perform a fault analysis.
[Kimura]
I found the operational analysis report (in Japanese) for this TMP, which was conducted in October 2021, so I am uploading it.
This TMP had experienced the same anomaly in October 2021 as it did this time.
Nakagaki, Uchiyama
We successfully extracted log data from the TMP at Y-10. We will send it to the company to investigate the reason for the trouble.