Modification of SORTEC RING and the Associate Machine Control
SystemPichit Keawbudta, Prayoon Songsiriritthigul, Takehiko Ishii, Goro Isoyama, Tatsuya Yamakawa,
Yutaka Hirata a), Naohisa Tsuzuki b), and Tamotsu Takeda b), National Synchrotron Research Center,Technopolis, Suranaree University of Technology, 111 University Avenue, Muang District, Nakhon
Ratchasima 30000, Thailand; a)New Energy Technology Department, Toshiba Corporation, 1-1-6
Uchisaiwai-cho, Chiyoda-ku, Tokyo 100-8510; b) Fuchu Works, Toshiba Corporation, 1 Toshibacho, Fuchu-shi, Tokyo 183-0057, JapanAbstract
Guidelines for building the control system of the firstsynchrotron radiation source in Thailand, named the Siam
Photon Source, are described. Central computers used for
Man-Machine Interface Stations (MMIS) are four personal
computers, three of which are usually used for indicating
status data transmitted from or to several Devices Control
Stations (DCS) through Ethernet. One unit of DCS
handles a group of equipment belonging to the major
component pieces of apparatus in the accelerator system.
Some details of the I/O connection will be mentioned
along with the descriptions of MMIS and DCS.

The Ministry of Science, Technology andEnvironment (MOSTE) of Thailand is now promoting thesynchrotron radiation research project named the SiamPhoton Project. The content of project has been reported
in various places [1-4]. The details of the Siam Photon
Source are also found in other articles [6-8].
The Siam Photon Project is summarized as follows:(1) A 1.0 GeV electron storage ring shall be constructed.
The storage ring shall be equipped with four longstraight sections for insertion devices.
(2) Beam lines and experimental stations for advanced
spectroscopic studies on gases, solid materials,
surfaces and interfaces shall be built. In the firstphase stage of construction, a complex beam line forangle-resolved photoemission and soft x-ray
fluorescence measurements shall be constructed.
(3) The installation of superconducting magnet wigglers
is considered. Beam lines for x-ray experiments
using light from the wigglers shall be built. The
experiments considered in the first phase stage isprotein crystallography.
(4) In the second phase stage of construction, beam lines
for other experiments shall be built. They include
thoseforsome
advancedphotoemission
spectroscopy,
x-ray
microscope,routinephotoabsorption and photoreflection experiments,
radiation biology, basic researches on metrology
using synchrotron radiation as an intensity standardof light, the study of micromachining, basic

researches on microlithography, and ordinary x-ray
crystallography.
The synchrotron radiation source built in the Siam
Photon Project is the modified SORTEC storage ring thatwas owned by the SORTEC Corporation in Tsukuba,
Japan. The SORTEC storage ring as well as theassociated injector linac, booster synchrotron and beamtransport lines were dismantled and the components weretransported to the National Synchrotron Research Center(NSRC) that is carrying out the practical work for theSiam Photon Project under MOSTE.
For the machine structure, we ask the readers to refer
the previous reports [1-7] in which the details of themodification of the SORTEC storage ring as well as theresults of the beam dynamics calculations are presented.
Concerning the machine control system that iscompletely renewed, a report describing an aspect different
from the present report is presented in this conference [8].
In that report, descriptions of the cause of the renewal of
the control system, the hardware and the software aredescribed.

The outline of the control system is as follows:
The control system forms a sort of local area network.
Sets of apparatus to be controlled are various instrument
controllers and power supplies broken up into groups
associated with the injector linac, the synchrotron, thestorage ring, beam lines and the pieces of equipment in
the control room. Data flow is made from the ManMachine Interface Stations (MMIS) to Ethernet and thento Devices Control Stations (DCS), Remote Input-Output
station (RIO), Subsystem Units (SSU), and Component
Units (CU). Obviously, the opposite data flow occurs
also. MMIS’s are the stations where operators makedialogue with the control system in a way as inputting
the order and operation parameters or obtaining theinformation on a deal of status of the machinecomponents. DCS’s are units where order or information
signals to and from various groups of equipment arerelayed. SSU’s are panels such as power supplies andcontrollers. CU’s are terminal units of the machine suchas magnets, the RF cavity, and beam monitors. Central

computers to be used for MMIS are four personal
computers, three of which are usually used for statusindication. Only one computer is used for controlling thewhole system. They shall be of the defacto standard. IBMPC is an example of this type. Information data aretransmitted from or to several DCS’s through Ethernet.
One unit of DCS handles a group of equipment belonging
to the major component pieces of apparatus in theaccelerator system. The DCS units to be set up are thosefor the linac and the low energy beam transport line, thesynchrotron and the high energy beam transport line, thestorage ring, the electric substation, and the system in thecontrol room. The input and output connection of a DCS
unit with various panels is made by computer linkdevices. They are RIO. The use of RIO drastically reduces
the numbers of wires connecting on-site panels withsystem interfaces. Nine interface panels shall be newlybuilt.

The personal computers, the sequencers, and component
parts for maintenance that are obtainable in Thailand shallbe used. As practical work, the following design work andmanufacturing work shall be carried out:
(1) The machines control equipment equivalent to that of
the SORTEC apparatus shall be designed and built
newly. The corresponding pieces of equipment are asfollows:(a) Interface panels for the power supplies to the low
energy beam transport (LBT) line system.
(b) On-site interface panels for the beam monitors inthe LBT system(c) Interface panels for power supplies in thesynchrotron(d) Interface panels for various power supplies in thestorage ring(e) On-site interface panels for beam monitors in thestorage ring(f) Computers for controlling the whole system(2) Interfaces for I/O connections for sets of equipment
added newly in the high energy beam transport (HBT)line system and those of the storage ring apparatus
shall be newly produced.
(3) Wires connecting computers for controlling the wholesystem with various pieces of equipment shall beprovided.
(4) The timing controller, the clock generator, the patternmemory, the beam monitor control panel, the interface
panel for the beam monitor and the interface panel forthe beam monitor that are from the SORTEC
apparatus shall be used in the present work.
(5) The signals from beam position monitor electrodes inthe storage ring shall be put in the signal processors.
The beam position monitor data out of the signal
processors shall be put in DCS.

(6) Processing of the signals for the OPEN/CLOSE statusof the beam shutters, however, shall be included in theglobal interlock of the safety system.
Some more additional explanations of the elements ofthe control system are presented blow.
(1) MMIS
Four personal computers at MMIS shall be driven by
Windows- NT 4.0. This is of the defacto standard. The
operation of the synchrotron radiation apparatus and theobservation of the machine state shall be performed with
MMIS provided here. The main functions of MMIS are as
follows:a) The computers exhibit the operational state,setting up of parameters and the start/stop
operation. The relevant operation and exhibition
are implemented independently for individualcomponent equipment.
b) Instruments requiring the sequence control arecontrolled by the computer at MMIS.
c) The MMIS computer makes and preserves theoperation pattern for the equipment that must beoperated by means of the pattern control. It
reforms the operation pattern, if necessary.
d) Three computers at MMIS are ready to show thealarm notice all the time. This is implemented byindicating the status whether important pieces ofequipment are in the normal operating states or outof order.
e) The three computers illustrate the aspect of thechange in the machine state.
f) The computers preserve the data of pressure in thevacuum chamber and the magnitude of the stored
current for a period of 24 hours.
g) The computers preserve necessary operation
parameter data for all sets of equipment.
h) The computers perform the global interlockcontrol.
(2) Interlock
The global interlock control shall be carried out. The
global interlock is the system that interlocks various
operation units using notice signals from various safety
devices so as to make the accelerators run safely. The
pertinent notice signals are as follows:(a) OPEN state signal from the beam stopper in theHBT system(b) ON signal from the fast kicker magnet power
supply of the synchrotron(c) ON signal from the septum magnet power supplyof the synchrotron(d) CLOSE state signals from the doors to themachine rooms and the experimental hall(e) OFF state signals from the manual switches forenergy stops(f) CLOSE state signals from beam line shutters

(g) NORMAL state signals from the access control
equipment(h) NORMAL state signals from the radiation safetycontrol equipment.
(3) RIOThe I/O connection of MMIS with various power
supplies and interfaces on the site are made through RIO.
RIO's are installed near the upper or side parts of thepanels. A number of RIO's on different panels connect inseries by means of Computer Link (direct connection
between computers with wires) and data are transmitted
through this line. The Computer Link line connects
ultimately with DCS described in (3). The interface
system for the I/O connection shall be provided formagnet power supplies, synchrotron beam monitors, LBTline beam monitors, storage ring beam monitors, HBTline beam monitors, the vacuum system, the RF
acceleration system, the clock generator, the timing
controller, and the pattern memory.
(4) DCS(a) DCS handles a group of equipment belonging to alayer through a number of RIO. DCS’s contain
Programmable Logic Controllers (PLC’s) that
control RIO's. Data from RIO's are transmitted toEthernet through DCS.
(b) The DCS’s to be built are shown below. If
necessary, further integration or division shall bemade.
Control Room DCS; Linac DCS; Synchrotron DCS;
Electrical Substation DCS; Storage Ring DCS

In conclusion, we summarize the functions of thepresent control system below. The functions are almost
the same as those of MMIS.
(1) Monitoring Operations of Individual Sets ofEquipment
Status indication, setting parameters, and making astart or a stop are made individually for various
pieces of equipment.
(2) Sequence Operation Control
The sequence control of the start/stop operations ofthe magnet power supplies and the RF power supply
are made.
(3) Production, Alteration, and Preservation ofOperation Patterns
The production, alteration and preservation of theoperation pattern of the magnet power supplies andthe RF acceleration system of the synchrotron aremade.
(4) Indication of Alarm Notice
The alarm notice shall be indicated if a sets ofequipment is in trouble.
(5) Indication of the History of the State Change
The history of the state change of a set of equipment
are illustrated.

(6) Preservation of Data
Data to be preserved are pressure in vacuum
chambers, the stored current, and necessary
equipment operation parameters.

REFERENCES
1. W. Pairsuwan and T. Ishii, J. Synchrotron Rad. 5(1998) 1173.
2. W. Pairsuwan and T. Ishii: Proceedings of the first
Asian Particle Accelerator Conference (High EnergyAccelerator Research Organization, Tsukuba, 1999) p.
3. W. Pairsuwan and T. Ishii: The Abstracts of the Third
Asian Forum on Synchrotron (Japanese Society forSynchrotron Radiation Research, Tokyo, 1997) p. 149
4. W. Pairsuwan, Prayoon Songsiriritthigul, Tatsuya
Yamakawa, Goro Isoyama, and Takehiko Ishii,
Proceedings of the International Meeting on theFrontiers of Physics, (Kuala Lumpur, 1998)
5. P. Kengkan, W. Pairsuwan, G. Isoyama, T.
Yamakawa and T. Ishii, J. Synchotron Rad. 5 (1998)
348.
6. G. Isoyama , W. Pairsuwan, T. Yamakawa and T.
Ishii: Proceedings of the XII-th National Synchrotron
Radiation Conference SR-98 held at Novosibirsk,
1998 (Siberian Synchrotron Radiation Center,Novosibirsk, 1998) p.
7. G. Isoyama, P. Kenghan, W. Pairsuwan, T.
Yamakawa, and T. Ishii: Proceedings of the first
Asian Particle Accelerator Conference (High Energy
Accelerator Research Organization, Tsukuba, 1999) p.
8. W.Pairsuwan, T. Ishii, G. Isoyama, T. Yamakawa,Y.Hirata, T. Takeda and N. Tsuzuki, Submitted to thePCaPAC’99 Conference held at Tsukuba in January,
1999.