Each product has its own specification, of course, there is also a self-healing fuse, so how do you view the specification of the fuse? This is very simple. As long as you know the meaning of the parameters in the specification, you can view the specification of self-recovery fuse clearly and quickly.
The meaning of "specification parameters" of self-recovery fuse is as follows.
I. IH (holding current): the maximum current that the polymer thermistor PTC can pass under the condition of no action in the static air environment at 25℃. Under limited environmental conditions, the device can be kept for an infinite time without changing from low resistance to high resistance. (the current passing through PTC is not enough to make the self-heating temperature rise of PTC exceed Curie temperature, which is called no-action current, and the maximum value of no-action current is called maximum no-action current);
Ii. IT (operating current): the inimum steady-state current of polymer thermistor PTC operating in a limited time under the static air environment of 25℃;
Iii. Vmax maximum voltage (withstand voltage): the highest voltage that the polymer thermistor PTC can safely withstand under limited conditions. That is, the withstand voltage of the thermistor. If this value is exceeded, the thermistor may be broken down and cannot be recovered. This value is usually listed in the withstand voltage column in the specification;
Iv. Imax (maximum current): the maximum operating current for safe operation of polymer thermistor PTC, that is, the current resistance of PTC. If this value is exceeded, the thermistor may be damaged and cannot be recovered. The value is listed in the current resistance value column in the specification;
Pd (typical value of power loss): in the static air environment at 25℃, the total value of power loss after PTC operation is obtained by calculating the product of leakage current flowing through PTC and voltage across thermistor.
6. trip: When the polymer thermistor PTC is too high, the polymer thermistor PTC changes from low resistance to high resistance;
Seven, Ttrip (action time): from the start of overcurrent to the completion of PTC action of thermistor. For any specific polymer PTC, the greater the current flowing through the circuit, or the higher the working environment temperature, the shorter the action time.
Eight, Tr (recovery time): refers to the time required to measure the resistance value of PTC thermistor to recover to twice the rated zero power resistance in the natural cooling process after operation;
Nine, Rmin (inimum resistance value): the inimum resistance value before PTC action in static air environment, the inimum resistance value before PTC action;
X. Rmax (maximum resistance value): the maximum resistance value before PTC action in static air environment at 25℃ before installation into the circuit;
XI. Ambient temperature: the static air temperature around the thermistor PTC or the circuit with thermistor PTC element;
Xii. maximum working ambient temperature: the maximum ambient temperature at which PTC elements are expected to work safely;
