Parts of electric and electronic equipment may be exposed to overheating stress due to the effect of electricity, and its deterioration may degrade the safety performance of the equipment. These parts should not be excessively affected by the heat and fire generated inside the equipment. Parts of insulating material or other solid combustible materials that are prone to flame spread inside the device may ignite due to a glow wire or a hot element. Under certain conditions, such as the fault current flowing through the wire, the element overloaded, and the poorly-contacted glow element light up.