Automated System for Calibration and Validation of Automotive Test Instrumentation

We describe the design and implementation of an automated calibration system for the thermocouple/voltage module of an automotive data-acquisition system. The automated calibration system tests and calibrates sixteen thermocouple/voltage signal-conditioning cards, with a combined total of 320 data channels, over the data-acquisition system's operating range from -40degC through +85degC. The system collects initial measurements to document on-arrival performance, calibrates each channel, and then collects final measurements to verify each channel's post-calibration function, all within an eight-hour period. The system also automatically identifies channels that fail calibration and flags them for repair. The automated system has eliminated more than 96% of the previous labor cost for calibrations, allowing us to recover the entire cost of development and equipment in less than one year.