Visit Mitsubishi Electric & Smarter Grid Solutions at booth #4617.

Discover new technologies in DERMS, Power Quality Compensators, Vacuum Circuit Breakers, autonomous substation monitoring, renewable integration and more. February 7-9, 2023 in San Diego, CA.
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Digital Rod Position Indication System (DRPI)

The DRPI System monitors and displays all control rod position information in the reactor core.

Critical to plant safety and operations, the system provides alarms to plant operators for a dropped control rod, and sends rod position data to the plant computer. Compared to analog RPI System, the DRPI System improves the precision of rod position detection and display. The Mitsubishi DRPI is implemented with the digital nuclear Instrumentation and Control (I&C) platform MELTAC®.

Mitsubishi provides all equipment needed to configure the RPI system including detectors, measuring circuitry and Human System Interface (HSI).

Diagram of digital rod position indication system

System Configuration

The Mitsubishi DRPI System is composed of the rod position detectors, prefabricated cables, the rod position ​​monitoring cabinet, and electrical-optical converter cabinet.

  • Rod position detector: Utilizes a stack of coil sensors to detect control rod positions. Transmits the rod position signals to the Data cabinet.
  • Prefabricated Cables: Transmits signals to the rod position monitoring cabinet.
  • Rod Position Data Cabinet: Receives discrete rod position signals from the detector and converts them to the digital signals. Then, transmits the rod position information to the E/O Convertor cabinet.
  • E/O Converter Cabinet: Receives rod electrical position signals from the data cabinet, and converts them into optical signals before sending to the Reactor Control System.

System Features

The Mitsubishi DRPI System is designed to minimize the effects of varying ambient temperature and magnetic permeability of the rod drive shafts.

  • The measurement is accurate within less than 6 steps
  • Compared to analog RPI, DRPI is less susceptible to temperature changes, can operate at higher temperature, and in generally more stable.
  • High reliability is achieved through application of redundant​ rod position detectors and interface circuitry
  • Rod position indication is displayed on the Visual Display Unit (VDU), which enhances information visibility.

Legacy Equipment

  • Assists in identifying and locating parts and component failures should they occur.

Other Products

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MELTAC Digital I&C Platform

Built around a common controller for both safety and non-safety related plant control functions.

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MR Computer

A distributed, industrial computer incorporating the MELCO real-time, POSIX-compliant operating system, MI-RT.

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Safety Protection System

Control and monitoring systems that support the safe operation of nuclear power plant safety functions.

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Control Rod Drive Mechanism Control System

The system commands and powers the control rod grippers that position the control rod cluster in the reactor core.

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Radiation Monitoring System

The RMS monitors dose rates and radiation levels at nuclear power plants.

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Nuclear Instrumentation System

An advanced design that allows for easier calibration and error detection with increased reliability and maintainability.

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Incore Instrumentation System

Measures neutron flux distribution in the reactor core and provides input to the core management computer.

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Turbine Electro Hydraulic Governor Control System

Manages steam flow to the turbine and can be applied to a variety of turbine generator system designs.

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Turbine Protection System

Providing an additional independent protection function for the steam turbine and generator.

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DIATOM

A flexible operator interface that improves the connection between the control room and facility monitoring systems.

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Reliable, Secure and Sustainable Energy Systems

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Industries

Energy systems to power a safe, sustainable, and secure future

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Services

Providing inspection, maintenance, upgrades and service for energy power systems

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Solutions

Turnkey engineering, design, logistical and project management solutions

We’re here to help.

Our expert sales staff have the knowledge, experience and vision to help you with your Power Generation requirements.

Contact Us