Nuclear movable element position indication apparatus, system, and method

An apparatus for monitoring a position of a control rod disposed in a nuclear reactor vessel disposed in a radioactive environment, the apparatus comprising:

• a processor coupled to a memory storing executable instructions, the processor located outside a containment structure;
• an analog multiplexer located in a data cabinet mounted on a nuclear reactor vessel head inside the containment structure;
• and
• a communication circuit coupled to the analog multiplexer and the processor;
• wherein when executed by the processor the executable instructions cause the processor to:
• (a) select a control rod position indicator coil arranged in a coil stack through the analog multiplexer, wherein the coil stack is located proximate to a control rod disposed in the nuclear reactor vessel;
• (b) pass an analog signal from the control rod position indicator coil through the analog multiplexer;
• (c) receive the analog signal from the analog multiplexer through the communication circuit;
• and
• (d) determine a position of the control rod based on the received analog signal.

A system for monitoring a position of a control rod disposed in a nuclear reactor vessel disposed in a radioactive environment, the system comprising:

• a data processing unit located outside a containment structure, the data processing unit comprising a processor coupled to a memory storing executable instructions;
• a nuclear reactor vessel located inside the containment structure;
• a plurality of control rods disposed in the nuclear reactor vessel;
• a coil stack comprising a plurality of control rod position indicator coils, wherein the coil stack is located proximate to the control rod disposed in the nuclear reactor vessel;
• a data cabinet mounted on the nuclear reactor vessel head inside the containment structure, the data cabinet comprising:
• an analog multiplexer;
• and
• a communication circuit coupled to the analog multiplexer and the processor;
• wherein when executed by the processor the executable instructions cause the processor to:
• (a) select a control rod position indicator coil arranged in a coil stack through the analog multiplexer;
• (b) pass an analog signal from the control rod position indicator coil through the analog multiplexer;
• (c) receive the analog signal from the analog multiplexer through the communication circuit;
• and
• (d) determine a position of the control rod based on the received analog signal.