The operating principle of JKPPTC Resettable Fuse is based on the dynamic equilibrium of energy. The curren passing JKPPTC component will cause some heat, part or all the heat diffuse in the air, while the stay heat can rise the temperature of JKPPTC component.(show in the under diagram)

1. Under normal working,the dynamic equilibrium of energy keep the JKPPTC’s temperature and resistance low. (T<25 ℃)
2. When the current or the environment temperature rising, but the heat produced and that sent forth still reach a equilibratory state, The JKPPTC will still in low resistance. (R<Rc,T<25℃)
3. When the JKPPTC’s temperature increaces to Tc,If the current and ambient temperature continue to further rise, then the stay heat will be larger and larger, thus causing the temperature of JKTTPC component abruptly rising. In this stage(Tc), the least change of temperature will cause resistance value substantially increasing, and JKPPTC component will be in the high resistance protection state(Rc~Rp,Tc~Tp). The increase of impedance will prevent current from rising ,and the current will rapidly fall in a little time,thus protecting circuit units from damage.
4. If the heat produced by the applied voltage is enough to the diffusing by the JKPPTC component , the component will remain in the operating state (high resistance).Once the applied voltage disappears, JKPPTC will automatically reset itself.