Cast Coil Transformer Fire Susceptibility and Reliability Study

This report investigates the fire characteristics and reliability of cast coil type transformers. A literature search was conducted and a questionnaire drafted requesting information from the manufacturers of cast coil type transformers. Abstracts from the National Fire Protection Association were reviewed to locate possible fires involving cast coil transformers. Testing was performed by the Idaho National Engineering Laboratory and independent testing firms. Results of this research and general industry usage indicate that cast coil transformers reduce risk to the user compared to liquid-filled units, eliminate environmental impacts, are more efficient than most transformer designs, and add minimal risk to the facility in a fire situation. Cast coil transformers have a long record of operation and have proven to be reliable and efficient.