Design of seawater radioactive on-line monitoring system

On-line γ radioactive monitoring system is designed for seawater γ radioactive detection, which the solenoid valve and water pump are controlled by IPC with digital I/O modules through the serial port communication. The dynamic and static measurement modes is decided with ultrasonic sensors and limit switches. Its software provides graphical user interface by which a series of setup auto measurement, manual control, energy spectrum monitoring and data save is completed. The five-point or seven-point filter is used in the software system to remove high-frequency noise. The test is completed with a depth of 3 meters, where the activity of ¹³⁷Cs is about 0.003 Bq/L and the activity of ⁴⁰K is about 12 Bq/L. The accuracy of peak finding is between 90% and 95%, performance test is passed with data integrity which equipment is normal. (author)