Detailed explanation of PPTC self recovery fuse

When traditional fuse is used as overcurrent protection , It can only play a protective role , After burning out, it needs to be replaced , A waste of time 、 Increase maintenance costs . Self recovery fuse , New overcurrent protection components , With protection 、 Automatic recovery dual function . that , About self-healing fuse , How much do you know ？ Tovo Electronics （DOWOSEMI）, Professional circuit protection device manufacturer , Have a deep understanding of self-healing fuses . Next , Walk into the world of self-healing fuses with Dongwo Electronics ！

Working principle of self recovery fuse

Self recovery fuse PPTC It is made of high polymer and conductive materials . Under normal circumstances , Conductive materials form three-dimensional conductive channels through polymer materials ,PPTC The resistance is very small ; When an abnormally large current passes ,PPTC The temperature rises rapidly , The polymer material then expands , Make the conductive channel disconnected , Cause a sharp increase in impedance , The current passing through becomes smaller , The circuit is like being disconnected , To protect . When the abnormally large current disappears , The self heating of the self recovery fuse is not enough to maintain its high resistance state , Its impedance returns to the low resistance state . Compared with traditional fuses ,PPTC With self recovery 、 Small size 、 High reliability and so on .

Action principle of self recovery fuse

The action principle of self restoring fuse is a dynamic balance of energy , Flow through PPTC The current is due to PPTC The relationship produces heat , All or part of the heat generated is emitted into the environment , And the heat that doesn't go out will increase PPTC Temperature of .

During normal operation , The temperature is lower , The generated heat and the emitted heat are in balance , So PPTC In low resistance state , No action . When flowing through PPTC The current increases or the ambient temperature increases , If the generated heat and the emitted heat balance are reached ,PPTC Still not moving . When the current or ambient temperature increases again ,PPTC Reach a higher temperature . If the current or ambient temperature continues to increase at this time , The heat generated will be greater than the heat emitted , bring PPTC Sudden increase of element temperature , At this stage , A small temperature change will cause a significant increase in resistance , At this time PPTC In high resistance protection state , The increase in impedance limits the current , The current drops sharply in a short time , So as to protect the circuit equipment from damage , As long as the applied voltage generates enough heat PPTC The heat emitted , In a changing state ,PPTC Then you can always be in the action state （ High resistance state ）. When the applied voltage disappears ,PPTC It will automatically return to the low resistance state .

Application field of self recovery fuse

Dongwo electronic self recovery fuse has various packages , Model is complete , According to the patch and direct insertion , Yes ：

Patch self-healing fuse PPTC：DW-USM(L) series 、DW-TSM(L) series 、DW-SM series 、DW-NSM(L) series 、DW-MSML series 、DW-ISM(L) series ;

In line self recovery fuse PPTC：DWPH series 、DWP75 series 、DWP60 series 、DWP33 series 、DWP30 series 、DWP16 series 、DWP06 series 、DWM series 、DWBV series 、DWBR series 、DWBN series 、DWLV series 、DWB series ;

Self restoring fuse is widely used , The main applications are ：

1） Telecommunications and Networks ： User terminal equipment 、 analogy / Analog line card 、T1/E1 equipment 、ISDN equipment 、ASDL equipment 、HDSL equipment 、 Main distribution frame security unit 、 Cable telephone / Cable from central office to users, etc .

2） Computer and multimedia ：CPU/IC The protection of the 、IEEE 802.3 Ethernet LAN、IEEE 1394、I/O port 、LCD The monitor / Monitor 、LNB Wei 、 Star set top box 、 The speaker 、PC Cards and slots 、 Smart card 、 Smart card reader 、DDC Video port DVI、USB、POS Equipment, etc .

3） Industry and automobile industry ： Electromagnetic load 、 motor 、 Fan 、 A hair dryer 、 Halogen lamp 、 Fire alarm equipment 、 Electronic ballast 、 Electronic safety device 、 transformer 、 Printed circuit board and copper platinum wire 、 Protect the electrical connection line / Harness, etc .

4） Batteries and portable electronic devices ： Lithium battery and battery pack 、 Protect the rechargeable battery pack 、 linear AC/DC converter 、 Protect the input port of portable electronic products 、DC Power converter of cigarette lighter, etc .

Specific selection of self recovery fuse 、 model 、 application 、 Parameters 、 Sample and other information , Consult Dongwo electronics directly ！