Self recovery fuse parameters, self recovery fuse symbol specification
A lot of small engineering and procurement personnel in self recovery fuse reading parameter information, often do not understand the meaning of symbols are used to represent what self recovery fuse, thus causing the trouble of reading, singing in this small series of electronic technology to bring you from the self recovery fuse symbol recovery fuse parameters description, hope to help everyone:
(1) the maximum operating current of the Ih self recovery fuse element at ambient temperature of 25
(2) It self recovery fuse element at 25 C ambient temperature to start the protection of the minimum current
(3) Imax self recovery fuse element can withstand the maximum current
(4) the maximum operating voltage of the Vmax self recovery fuse element
(5) Vmaxi self recovery fuse element in blocking state under the maximum voltage
(6) since the resumption of Rmin initial minimum resistance of fuse element before work
(7) Rmaxi self recovery fuse element at the end of work before the initial maximum resistance Hold current Ih keep current is self - fuse series high polymer PTC thermistor to keep the maximum current that can pass through without action. Under the condition of limited environment, the device can be kept for a long time without changing from the low resistance state to the high resistance state.
Action current It in a limited environmental conditions, so that the self reset fuse series polymer thermal resistance in a limited time action of the minimum steady-state current.
The maximum current Imax (flow resistance value) in a limited state, self reset fuse series polymer PTC thermistor safety action of the maximum action current, that is, the resistance of the heat sensitive resistance. Over this value, the thermal resistance is likely to be damaged and cannot be recovered.
The efficacy of Pdmax in the circuit under normal operating conditions of the polymer self recovery fuse in the circuit consumed by the effectiveness of
The maximum working resistance Vmax polymer self recovery fuse work can withstand the voltage, if the voltage is too high, then the self recovery fuse device is likely to circuit protection failure or error protection
The maximum voltage withstand voltage of Vmaxi polymer resettable components can withstand the maximum, if the voltage exceeds the value of self recovery fuse components is likely to damage failure, can not effectively protect the circuit
The initial resistance Rmin before being mounted to the circuit in the condition of the environment temperature is 25 DEG C under test, since the complex polymer PTC thermistor fuse series resistance.
The initial maximum resistance of Rmax at room temperature, resettable fuse series polymer PTC thermistor action or reflow soldering installation to the maximum resistance after an hour in the circuit board measured value.
What is the relationship between IH and IT? Why is there a difference? The relationship between IT and IH is the 2:1 of most of our products. Some products may be as low as 1.7:1 while others may be as high as 3:1. Materials, processing methods and the different forms of heat resistance of the IT and IH are different. The actual ratio of most of our products is 2:1.
Rmin, Rmax and Rl what is the difference? In the specified conditions (e.g., 20 degrees C), the resistance values of the pre specified self recovery fuse are in a range of values, that is, between the minimum (Rmin) and the maximum (Rmax). High polymer PTC thermistor at room temperature action after the end of 1 hours after the resistance of the maximum value or welding to the circuit board one hour after the resistance value of Rl.
The above parameters about self recovery fuse, self recovery fuse symbols provided by Shenzhen tergytech Co. Ltd. technology department! Thank you for reading.