Automated Bicron Tester: Automated electronic instrument diagnostic, testing, and alignment system with records generation

摘要

The Bicron Surveyor MX is a portable radiation monitoring instrument used by the Office of Radiation Protection at Oak Ridge National Laboratory. This instrument must be calibrated in order to assure reliable operation. A manual calibration procedure was developed, but it was time consuming and repetitive. Therefore, an automated tester station that would allow the technicians to calibrate the instruments faster and more reliably was developed. With the automated tester station, calibration records and accountability could be generated and maintained automatically. This allows the technicians to concentrate on repairing defective units. The Automated Bicron Tester consists of an operator interface, an analog board, and a digital controller board. The panel is the user interface that allows the technician to communicate with the tester. The analog board has an analog-to-digital converter (ADC) that converts the signals from the instrument into digital data that the tester can manipulate. The digital controller board contains the circuitry to perform the test and to communicate the results to the host personal computer (PC). The tester station is connected to the unit under test through a special test harness that attaches to a header on the Bicron. The tester sends pulse trains to the Bicron and measures the resulting meter output. This is done to determine if the unit is functioning properly. The testers are connected to the host PC through an RS-485 serial line. The host PC polls all the tester stations that are connected to it and collects data from those that have completed a calibration. It logs these data and stores the record in a format ready for export to the Maintenance, Accountability, Jobs, and Inventory Control (MAJIC) database. It also prints a report. The programs for the Automated Bicron Tester and the host are written in the C language.