The Principle and Characteristics of PTC Heater
1.What are PTCs?
PTC is the abbreviation of "Positive Temperature Coefficient", that is, "positive temperature coefficient". Since the ceramic semiconductor has a large positive temperature coefficient and its resistance increases with temperature, it can be used as a heating element. Its positive temperature coefficient allows electric current to flow better at low temperatures than at high temperatures; as the temperature rises, its current conductivity and power output decrease until an equilibrium state is reached, at which point the current flow can hardly continue Flow, this is the so-called PTC effect. Due to its self-regulating properties (temperature self-limiting), the PTC heating element does not overheat, so this heating technology is particularly safe and reliable.
2.Everything is possible with PTC
Safe Heating
Based on the PTC effect, the PTC heating element will not exceed its fixed upper temperature limit, so it can be safely heated without additional protection even under the second level of protection.
Effective Heating
The PTC heating element will adjust its performance with the change of the environment, so it can save energy consumption when the heat dissipation is slow, and the heating performance can be guaranteed without additional temperature control equipment.
General Heating
PTC heating elements can operate at near-constant power over a wide voltage range, and the relevant standards are internationally recognized for your peace of mind.
3.PTC characteristic curve
The PTC curve refers to this typical function curve, which represents the relationship between the resistance of a semiconductor and the temperature. Initially, the resistance of the PTC decreases as the temperature increases until it reaches the minimum resistance value Rmin. After that, the characteristics of PTC began to show, and its resistance increased non-linearly until the rated temperature Tc, which is also called "Curie temperature", at which time the resistance of PTC increased significantly. The PTC's operating range extends from Tc to a maximum final temperature Te where hardly any current flows. The maximum temperature of a PTC depends on its ceramic composition and can therefore be specified in advance. Another characteristic of PTC is its inrush current. Since the resistance of the PTC is at its lowest value in Rmin, it can allow a particularly large current to pass through it, causing it to have a few seconds of inrush current increase every time it is switched on.
