The working temperature of the electric heating plate of the household dining table is moderate, and the warm food maintains the heat balance at 70-80℃, which can make the food not only have a certain degree of heat, but also maintain its original flavor and color. Electric heating insulation board made of PTC constant temperature heating element. Experiments have proved that this new type of electric heating plate has the characteristics of constant temperature, limited temperature, low power consumption, fast heating, strong heat preservation ability, wide adaptable voltage range, simple structure, safe and reliable use, and low cost. The table is kept warm or used for baking bread, warm breakfast, tea, coffee, etc. Due to the room temperature heating characteristics of the PTC heater, for a predetermined thermal system (designed insulation board), at a certain ambient temperature, the electrical power consumption of the system does not change much under different voltages. Within a certain voltage range, the power consumption characteristics and surface temperature rise characteristics of electric heating plates under different voltages are also very similar. PTC electric heating plate can adapt to a wide operating voltage range, especially in areas with lower power supply voltage, PTC electric heating plate can also provide good results. The working characteristics of the PTc electric heating plate are related to the heat transfer state and the ambient temperature. Therefore, PTC heating elements are very ideal electric heating plates.