Improvement of Temperature and Humidity Measurement Systemfor KEK Injector Linac

THMPA07

I. Satake, M. Satoh, T. Suwada, Y. Yano, High Energy Accelerator Research Organization (KEK), Tsukuba, JapanT. Kudou, S. Kusano, Y. Mizukawa, Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan

Conventional Measurement System

KEK Injector Linac– Total length is about 600 m– The ground floor (klystron gallery) and underground floor(tunnel).
– Klystron gallery is divided into sectors of about 80 m. A partof device name (EPICS PV name) includes sector name.

 The system is introduced to monitor the temperature, which is ameasurement target for a large number of devices indispensable for
operation of the injector Linac and its surrounding environment.

Stable operation of the injector Linac⇒ The temperature of each operating device Table 1: Requirement ofCooling Water
and its surrounding environment are very
Temperature Stability
important information.

Alarm system– Limited number of subsystem aremonitored by temperature sensors(accelerating structure cooling water,
inside tunnel, inside gallery) CSS archiver viewer:
The web application to monitor
the temperature and humidity data.

– However, it takes some time to display long-term data for retrieving thelarge amount of data points.

Fig. 1: Schematic layout of the KEK
injector Linac.

System Description

Fig. 2: CSS archiver viewer.

Table 2: Type and Number ofMeasuring Object

 The temperature measurement system has the total
number of 720 sensor units consisting of resistancetemperature detector (RTD, Pt 100), thermocouple (K),humidity sensor, and 26 data loggers.

Fig. 3: Picture of the data logger.

Fig. 5: Measurement object.

Fig. 6: Schematic layout of data loggers forthe temperature and humidity measurement
system at the KEK injector Linac.

Fig. 4: Picture of the sensor.

Data Acquisition Software

8 sector
× 3~4 units

New Alarm System Software

 EPICS IOC stores information that the data logger has collected andstored into EPICS PV. The CSS archiver engine acquires EPICS PV
data and records them into PostgreSQL which is a Relational
Database Management System (RDBMS).
CSS archiver :standard tool fordata logging in
EPICS system
Measurement
data via all 26
data loggers ismanaged by only
one EPICS IOC.

Fig. 8: Image example of the new archiver data viewer and alarm
display panel for managing temperature and humidity.
Fig. 7: Schematic layout of data acquisition software
for the temperature and humidity measurement
system at the KEK injector Linac.

New Measurement System Software
We developed a new panel for temperature measurement system basedon Python, using matplotlib which is a standard library for drawing
graphs in Python. We also used Tkinter, a standard library for building
and manipulating GUIs in Python.
– Data is packed every hourand saved as a text file.
– Functionality of selecting
PV by type and place⇒ Display speed for dataof large amounts orlong period
 Operability for
multiple data display

 The new alarm system determines the threshold by calculating thestandard deviation value from the data obtained during a certain period.
This threshold is set in the alarm field of EPICS PV. In every 10 seconds,
the CSS alarm monitors whether the current data is anomalous.

Summary and Future Plan By using the newly developed software, we have been able to monitor
the temperature and humidity of various devices affecting the beam
operation and quickly detect defects of the measurement data.
 Usability of the panel during operation was drastically improved.

＜ Plan ＞• Calculation of the more appropriate alarm threshold by thetest during daily beam operation• Detecting the defects of the status for other subsystems(rf phase, magnet, etc.) by introducing this alarm system
Fig. 9: Image example of the new archiver data
viewer for managing temperature and humidity.

We will contribute to the daily stable beam operation of the injector Linac
through the quick detection of anomalous temperature and humidity
fluctuation for the large number of Linac control equipment.