What is the level of electrical power that can create ignition? What size resistance comprises a high resistance connection? Will arcing result from low-energy ignition? Can Class 2 transformers cause ignition? Answers to the first three questions identify the electrical parameters involved in low electrical energy fires. Class 2 power supplies are very common electrical sources for low electrical energy. The common perception is these supplies are inherently safe, and are incapable of being a source of ignition. By design, the transformers are safe except under a near-short condition. Results of experimental research provide fascinating new insight into these issues. The electrical energy required for ignition is surprisingly low.