Real Time Monitor on the Internet for the Experimental Apparatus
Shigeru Ishimoto, Syoji Suzuki and Tsuneaki Tsuru
KEK, Tsukuba, JAPANAbstract
The control and monitor of the experimental apparatus
by Personal Computers (PCs)[1][2] become very
common. Recently, we have developed a simple program
to capture the PC screen and save it as GIF or JPEG files
periodically. The experiment E-248 (AIDA) "Search for
H-particle in the reaction of pp -> K++K++X"[3][4] at
KEK-12GeV-PS used the super conducting spectrometer
magnet "BENKEI"[5] and the liquid hydrogen target[6][7][8][9]. These low temperature devices werecontrolled and monitored by the PCs. MicrosoftWindows95 was used as an operating system (OS) andPersonal Web Server (PWS) was installed for the use ofthe Web server. The PCs were connected to the LAN and
the Internet by TCP/IP. The numerical data of theinstruments were stored to the FTP root-directory\webshare\ftproot\ on the hard disk drive (HDD) in every
1minute. These data were monitored on the Internet using
auto-reload mode by the WWW browser. The stored data
were transferred by the FTP to the other computers. ThePC graphic data were captured as a BMP file, werechanged to a GIF file and transferred to the WWW rootdirectory \webshare\wwwroot\ in every 5 minutes. TheGIF files were monitored on the Internet by the HTTP andthe WWW browser with the auto reload mode. This realtime monitor on the Internet can be used for wide fields
using PCs.

(A) Monitoring of the temperature, pressure, LHe/LN2levels and vacuum etc.
(B) Monitoring of the GHe flow-rate which cools themain current leads, and operation of theemergency valves that open to the air when theGHe recovery line was blocked.
(C) Set and automatic control of the pressure
difference between the LHe Dewar and theBENKEI, during the LHe transfer.
(D) Automatic LN2 supply(E) Alarm of the devices and some logical alarms (ex.
LN2 empty).

1. APPARATUS AND PC
MONITORING SYSTEMS
1.1 Super Conducting Magnet BENKEIBENKEI is a S.C.-Magnet with a large aperture and aniron return yoke. It has an accumulated energy of 3.15
MJ, a cold mass of 5.64 t, a total weight of 16.3 t, a LHetank of 300 l and a LN2 tank of 120 l.
In the time of the AIDA experiment, we had to operate
BENKEI safely at maximum current of 610 A without aquenching. The LHe of about 200 l was transferred to themagnet, twice in a day. During the LHe transfer, we had
to operate it without a thermal oscillation nor a large
differential pressure of two current ports which makes aquenching because the LHe level becomes low.
A schematic sheet of the BENKEI control system isshown in Fig. 1. Input/output devices were ADC, DACand DIO boards that were inserted to the expansion-bus ofPC (NEC PC-9821Xa: Intel Pentium 200 MHz). The PC
controlled the following items.

Fig. 1 The super BENKEI control system

1.2 Liquid Hydrogen Target
The target cell is a cylinder made of a thin stainlesssteel and its dimensions are 0.05 mm of thickness, 50
mm of diameter and 250 mm of length.
The H2 vapour pressure and the temperature should becontrolled precisely as much as possible to keep the liquiddensity and the shape of the cell constant, and also toprevent a fatigue of the metal. For this purpose, we used ahigh-precision pressure transducer “Baratron” with athermal stabiliser. A heater at the condenser was PID
controlled by the PC to be at the pressure of 1.05 kg/cm2.

A schematic view of the LH2 target control system by
the PC (NEC PC-9801BX4: Intel 486DX4-100 MHz) are
shown in Fig. 2.
The acquired data by a data-logger are transferred to thePC. The control signals from the PC are sent to DC
power supplies and a relay unit etc. via GPIB-bus.
The distance between the PC and the control-rack wasextended to about 30 m with a pair of GPIB bus-extenders
and a coaxial cable.
The PC controlled the following items.
(A) Monitoring of the temperature, pressure, liquidlevel, vacuum and leak of GH2. Calculating of theheater power from measured DC-current and DCvoltage. Conversion of the temperature from PtCo
resistancethermometers
andC-C
thermocouples using the calibrated data.
(B) Automatic pressure/temperature control for theLH2-condenser as mentioned above.
(C) Alarm control for the monitoring values and somelogical alarms. Logical alarms will turn off therefrigerator, the compressor, and the heater, andturn on the warning buzzer. In addition, digital
voltmeters with relays were used to make thehardware protection circuits when the PC hang up.
(D) Remote on/off operation of the devices from PCkeyboard. Graphics and status-display of the pastand present data of the refrigerator and thecompressor.

2.

NUMERICAL DATA ON THE
INTERNET

2.1 Upload to UNIX Host by MS-DOS(BASIC)First, we uploaded the text data periodically to theUNIX host (psux1.kek.jp) by the monitoring program
made by NEC N88-BASIC on MS-DOS via RS-232C
port and KEK-LAN. The latest data are visible from any
remote login terminals by using a simply shell-scripts in
UNIX host for periodical display. To watch the data fromthe WWW browsers (anonymous access), we wrote thedata in the HTML format by the monitoring program andput it to $HOME/public_html/ directory in the UNIXhost.
In the HTML text data, we described <META HTTPEQUIV="REFRESH" CONTENT=60>. This command
will auto reload the data in every 60 second.

2.2 Use WWW Service under MS-Windows95
Second, we used the Personal Web Server under MSWindows95 (the Peer Web Services or the IIS if using
MS-WindowsNT 4.0) in the same PC for control andmonitor, in order to shorten the upload time and reduce
the CPU load.
2.2.1 WWW Service
In the monitoring program, numerical data are directly
saved to \webshare\wwwroot\ on the HDD in almost 0.1
second without loss of the transfer time to the network.
This saving time to the HDD is negligible in thecondition that the data taking intervals are 10 to 16 sec.
If it is necessary, we can reduce the interval time to one
tenth, but it was enough to monitor our cryogenic
apparatus. The method to save the data in HTML format
to the directory of PC Web service, are very easy way topublish the experimental live data on the Web.
2.2.2 FTP ServiceFig. 2 The LH2 target control system

In every 20-30 monitoring cycle, the logging data aresaved to \webshare\ftproot\ as a text file aside from thedata saving for WWW browsing.
The data size and logging times are followings.
BENKEI: 1 file 20 data, 5541 bytes/file and 3.3 min /file,
LH2 Target: 1 file 30 data, 23958 bytes/file and 8.4 min/file (1 data = acquired data from all channels in 1 cycle).
These stored data were manually transferred and saved toother PC by the FTP service.
If the monitoring program has a subroutine to read asetting file from the FTP directory, we can remotely
control the apparatus via the Internet. In this case, in order
to avoid the security problem, we can set an accesslimitation for the Internet service, for example passwordset.

3. GRAPHIC DATA ON THE
INTERNET
3.1 Capture and Save the PC Display
Resolution of the display on the MS-Windows95 was
800_600 dots, 256 colours and the MS-DOS window forthe monitoring program was 640_480 dots. Manual way
to capture the screen is to push “COPY-key” on NEC
PC-9801 or “Print Screen-key” on the IBM-PC/AT
compatible. The captured graphic data have to beconverted to GIF or JPG format to use in the Web.

3.2 Batch Process under MS-Windows95
For the automatic operation of this process, we used abatch program, a capture program and a graphic converter
program. These programs can be operated in the Win32
native mode. The batch program runs aside from themonitoring program under the multitask mode andperforms the jobs, capture the screen, convert the BMP
file to the GIF file, delete the BMP file and wait interval
time. We used “WinBatchEh ver1.27”[10] as the batch
program, “CliPlu ver1.0”[11] to capture and save theBMP file and “RASTRN ver1.6”[12] to convert the file
into GIF format.
These 3 programs are shareware or freeware.

4.

RESULTS AND CONCLUSION

We have performed a real-time monitor by using theWWW browser via the Internet for the acquired numerical
data and the desktop view on a controller PC. We also
obtained capability to transfer the logging data by using
the FTP from remote machines.
These monitor and control systems were successfully
operated through total about 1 year. This method had agreat advantage for the view of safety and also for theview of easier experimental monitor and control.
When we need higher speed system, it will be possible
by using powerful PC or using better programming
languages. Recently, we have developed and successfully
tested a new program by Visual Basic on Windows95/NT
to capture the PC (IBM-PC/AT or NEC PC9801) screen,
and transfer to the Internet. This simple method tomonitor the apparatus on the WWW can be applied towide area of the experiment using PC system.

3.3 Views through the WWW Browser
Fig. 3 and Fig. 4 are examples of graphic data on theNetscape Navigator Gold 3.0. The upper part of graphic
window is for numerical data obtained from ADC/DI ordata-logger, the lower part are the graph of the numerical
data. Time axes are in full scale of 24 hours, and after 1
day the old data will be erased.
It took about 2 sec to capture the screen, convert theformat and save the data to the HDD by the PC of
486DX2-100 MHz, and it took about 1 sec in case of thePentium 200 MHz.
Fig. 4 PC-desktop view of the LH2 target

REFERENCES[1] S. Ishimoto et. al., Bonn, Proceedings, High energy
spin physics, vol. 2(1990)369[2] N.Hayashiet.
al.,Nucl.Instrum.Meth.
A356(1995)91[3] H. Kawai et. al., E-248(AIDA) KEK-PS proposal at
KEK, in Japanese.
[4] S. Fukui et al., Proceeding of the Workshop on
Hadron Physics at e+e- Collider, IHEP, Beijing,1994[5] T. Inagaki et. al., Cryogenics 24(1984)83[6] S.Ishimoto and S.Suzuki and T.Tsuru, KEK Report
97-4, June 1997, H/D[7] M. Kobayashi et. al., Jap.J.Appl.Phys. 24(1985)593[8] T. Sumiyoshi et. al., J.Appl.Phys. 22(1983)1606[9] S. Isagawa and S. Suzuki, KEK Int. 82-13(1983)[10] WinBatchEh. ver1.27 by Youhei Shimizu.
[11] CliPlu ver1.0 by PUTO.
[12] RASTRAN ver1.6 by Kamiya
Fig. 3 PC-desktop view of the super BENKEI