Ⅱ-8. Accelerator

RIKEN Accel. Prog. Rep. 49 (2016)

New operation interface for rf voltage and phase of RIBF cyclotrons
using rotary encoder
K. Yamada,∗1 S. Ishikawa,∗2 R. Koyama,∗2 K. Yadomi,∗2 and N. Sakamoto∗1
The RIBF accelerator complex can accelerate allkinds of ions up to β = v/c = 0.7 via a four-stage
cascade of ring cyclotrons, i.e., the RIKEN Ring Cyclotron (RRC), fixed-frequency Ring Cyclotron (fRC),
Intermediate-energy Ring Cyclotron (IRC), and Superconducting Ring Cyclotron (SRC). The rf systems forthese cyclotrons are controlled by using an individual
programmable logic controller (PLC) for every rf resonator. The remote control interface for the fRC, IRC,and SRC accomplished in 2006 has been actualized byan Ethernet connection to PLCs using a PC base driverand SCADA software of Wonderware InTouch 9.5. The
remote control interface had some problems such as
slow response and disconnection of network owing to
the use of an older-generation PLC. Thus, we have constructed a new operation interface to remotely control
the rf voltage and phase using rotary encoders suchas that for the RRC instead of using mouse clicks inorder to realize smooth and comfortable operation ofthe cyclotrons.
Figure 1 shows a schematic of the new remote control system. The remote control interface is directly
connected to an additional PLC (OMRON CS1H) installed in the control room. The signals of rotary encoders are counted by fast counter modules of the PLC
and converted to set point data for the rf voltage andphase, which are stored in the PLC memory. The data
are distributed to relay PLCs installed in the vicinity of the existing RF control PLCs for the fRC, IRC,and SRC through a private data link network using
Controller Link. Each relay PLC is connected to theexisting RF control PLCs via an open field network,DeviceNet, because the existing PLCs were alreadydiscontinuous product but they had been incorporated
in the DeviceNet master module.
As shown in Fig. 2, two hardware buttons, eight rotary encoders, and a touch panel are mounted on theinterface. One of the hardware buttons is a LOCK
button and the other is a SET button similar to theRRC interface. The control inhibition has to be released by the LOCK button to start the operation using encoders, and the control is automatically inhibited
after 3 min. A control target cyclotron, fRC, IRC, orSRC has to be selected using the touch panel. Whenthe lock is released, the all present set points of the rf
voltage and phase on the existing RF control PLCs areimported to the memory on the PLC installed in thecontrol room, and the operation using the conventional
PC base control is invalidated, which ensures compatibility. The group of rotary encoders on the left isfor rf voltage control, whereas the group on the rightis for rf phase control. The voltage setting of all therf resonators can be adjusted individually. The phasesetting of the main acceleration resonators is adjusted
using a rotary encoder simultaneously, and the phasesetting of the flat-top resonator is adjusted independently. All the present values of voltage and phase,
set points, and control step sizes are indicated on thetouch panel. The control step size can be selected using the touch panel. The present set points can besaved to memory by pushing the SET button up toten times.
The new system was successfully commissioned inMarch 2015 and was operated during the RIBF experiments without problems. Owing to the introductionof the new interface, smooth operation with a response
ten times faster than that of previous systems and nonetwork connection issues will lead to optimum tuningof the rf voltage and phase for the RIBF cyclotrons.

Fig. 1. Schematic of the new remote control system for
RIBF cyclotrons.
∗1∗2

RIKEN Nishina Center
SHI Accelerator Service Ltd.

Fig. 2. Remote control interface for the new system.

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