Decomposed Functional Behavior of Helium Purification Support System for Experimental Power Reactor (RDE) Type Using Sequence Diagram

Abstract
Instrumentation and Control (I&C) system in Nuclear Power Plant (NPP) has a key role to maintaining the safety and control the integrated system to operate the NPP. The aim of helium purification instrumentation system in High Temperature Gas-cooled Reactor-test Module (HTR-10) reactor is to reduce chemical impurity levels in the primary helium cooling system and to eliminate the fission products of radionuclide gas. Indonesia conduct a research about Experimental Power Reactor (RDE) with HTR-10 type of reactor, then the helium purification system has an important role since this reactor will use helium in the primary cooling system. Since this HTR-10 type of reactor is had been develop by Tsinghua University in China since 1995, then for development of RDE in Indonesia should refer to the initial design of HTR-10 from China, and continuing to improve the design by decomposed the system function so that RDE design will more safety and reliable. After decomposed the new system of helium purification, the sequence diagram of helium purification will developed to review the new system function of helium purification instrumentation. Sequence diagram is system engineering methodology which can help the design engineer or system engineer to understand the system behavior by mention in to important requirement of the system. By this sequence diagram, it hope that the design engineer will clearly understand the functions and translate in to design synthesis and architectural design in the next step of development phase of helium purification I&C system.
Kussigit Santosa, Restu Maerani and Sudarno