Self recovery fuse principle
Self recovery fuse is made of conductive particles which are specially treated and distributed in the inside. In the normal operation of polymeric resin tightly conductive particles bound in the crystalline structure, form a chain conductive circuit, self recovery fuse is in a low impedance state at this time, the line passes through the heat generated from the current recovery fuse is small, does not change the crystal structure. When the circuit overload or short circuit occurs, large current flows through self recovery fuse the heat polymerized resin melt volume, rapid growth, forming a high resistance state, the working current decreases rapidly, and thus restrict and protect the circuit.
Two, self recovery fuse working principle
Self recovery fuse is made of specially treated polymer resin (Polymer) and the distribution of conductive particles (Black Carbon) in it. In the normal operation of polymeric resin tightly conductive particles bound in the crystalline structure, form a chain conductive circuit, self recovery fuse is in a low impedance state at this time (a), the line passes through the heat generated from the current recovery fuse is small, does not change the crystal structure. When the circuit overload or short circuit occurs, large current flows through self recovery fuse the heat polymerized resin melt volume, rapid growth, the formation of high resistance state (b), the working current decreases rapidly, and thus restrict and protect the circuit. When troubleshooting, self recovery fuse re cooling crystallization, volume shrinkage, conductive particles to form a conductive path, self recovery fuse to restore the low state of resistance, so as to complete the protection of the circuit, without manual replacement.
Three, self recovery fuse action principle
Since the action principle fuses a dynamic balance of energy, through the self recovery fuse current series of elements due to the relationship between the self recovery fuse series of heat, the heat generated in whole or in part is dissipated to the environment, without dissipating heat will improve the self recovery fuse series element temperature. Normal working temperature is low, the heat and the heat emitted to the balance. Self recovery fuse series element is in a low state of resistance, self recovery fuse series of action, when flowing through the current self recovery fuse series element or environmental temperature increased, but if the heat and heat radiated from the balance, self recovery fuse series is still not moving. When the current or ambient temperature is further increased, the self recovery fuse series will reach a higher temperature. If the current environmental temperature or continue to increase, the heat generated will be greater than the heat dissipated, the self recovery fuse series element temperature surge, at this stage, very small temperature changes will cause a substantial increase in resistance, then the self recovery fuse series element in the high impedance state protection, impedance increase limits the current. The current decline sharply in a very short period of time, so as to protect the circuit equipment from being damaged, as long as the applied voltage which generates enough heat to self recovery fuse series element gives off heat in the self recovery fuse series element condition can be always in motion state (Gao Zu). When the applied voltage is lost, the self recovery fuse series can be automatically recovered.
Four, self recovery fuse application principle
Since the restoration of the fuse can provide lights in the use of the time limit for the protection and fault protection of the transistor. Because the ballast often fails because of the voltage switch on the upper and lower ends of the transistor, the fault protection of the transistor is of great significance. First of all, the resettable fuse with performance can be automatically restored, the number of products can reduce the repair and service, thereby reducing the cost. Secondly, since the volume of the fuse is small, the space occupied by the circuit board is small, which is convenient for the design.