A temperature excursion occurred in a sealed environmental chamber during a 0°C ambient temperature test. An elevated temperature in the chamber resulted in a small fire that was confined to the environmental chamber. Visual observation indicated no damage to nearby equipment, including nearby computer cables.

A committee was assembled with the task of identifying the cause of the incident. The committee concluded that the fire was caused by failure of the heater control system for the environmental chamber. The failure of the heater control system caused the chamber temperature to eventually exceed 200°C. As the chamber temperature increased, plastic materials and electrical insulation present in the chamber started to decompose. A battery scheduled for testing was also located view more