Taking the (emotional) stress out of HALT

The HALT process used at Rockwell Automation takes a product, printed circuit board, or component through five test sequences: low-temperature step-stress, high temperature step-stress, random vibration step-stress, combined temperature cycling/random vibration, and rapid temperature cycling. The temperature or vibration amplitude where any anomaly occurs, as well as the time, relative to the start of the test sequence, is noted. For each anomaly that occurs, a temperature and vibration robustness factor is calculated. The robustness factor is then translated to a probability of occurrence. Additionally, the severity of each anomaly is independently evaluated by engineering and quality functions in terms of severity of the effect on warranty, operation, and safety. The independent severity assessments are then combined into a composite severity. Recommended actions for remediation of each anomaly are made based on the occurrence and severity assessments using a HALT Action Matrix. This anomaly assessment process has eliminated the emotional arguments between various functions about remediating HALT anomalies and has ultimately benefitted the customer as more anomalies are being fixed than before the HALT Action Assessment process and tool were introduced.