Electric Vehicle PTC Heaters

Positive temperature coefficient (PTC) heaters bring efficiency and safety to EV heating systems. The heating element inside a PTC heater has a positive temperature coefficient and its resistance increases with temperature. When power is first applied to the cold PTC heating element, it has a low resistance and draws a large amount of current. As it heats up, the resistance increases and the current draw decreases. This makes a PTC heater inherently both safe and efficient; the PTC heater will stop drawing current if it overheats and it only draws the current it needs to maintain temperature. A PTC heater also heats faster than a traditional element, as it draws maximum current when it is cold.