Self recovery fuse Selection Analysis Guide: self recovery fuse is a overcurrent protection and electronic components, using organic high molecular polymer in high pressure, high temperature, vulcanizing reaction conditions, adulterating the conductive particle materials, through special processing and. Used to call the PPTC self recovery fuse. Self recovery fuse is used to do the main role of the flow of electrical protection. Therefore, the self recovery fuse has the parameters such as voltage, current, operating time, etc.. Therefore in the self recovery fuse type selection is based on the products used in the voltage, current and current protection, etc. to choose the right products.
1, the average operating current (I) and maximum operating voltage (V) on the device line are listed.
2, lists and range of the normal values of temperature in the working environment, according to the reduced rate of normal current IH (see the environment temperature and the current value of the discount rate) IH = average operating current (I) 83019 environment temperature and current value of fold reduction rate (related knowledge: electronic components of PTC and NTC effect is not what)
3, according to the L, V value, product categories and installation method to choose a kind of self - complex fuse series. (refer to each specification sheet)
4, selected from complex fuse I value must be less than or equal to the IH, rated current is under certain conditions are given, if required to work in a wide temperature range should be left a certain margin, take 1.5-2 times.
5 according to the model of the action time curve of the self recovery fuse to confirm whether the selected products meet the requirements of the action to protect the time.
6 control specifications provided by the data, confirm the specifications of the thermistor size to meet the requirements.
7, because it is a semiconductor polymer devices, so the number of switches will not be less.
8, the use of attention when it has a certain resistance, the greater the current rating, the smaller the resistance; high voltage resistance to a greater number of.
For example, a control circuit needs to be over current protection, the operating voltage is 48 volts, the circuit is normal operating current of 450 Ma, the circuit environment temperature is 50. When the current in the circuit is reached 1.4 ampere, the protection and the circuit can be quickly protected for 2 seconds in 5 seconds. We can according to the working voltage of 48 V, first select the voltage level for 60 VOLTS wh60 series self recovery fuse products, and control of the series of products to maintain the list of current and temperature relationship Wh60065 or Wh60075 two kinds of specifications of products, according to the action and the current diagram found, 5 ampere action time of Wh60065 wh60-075 for about 1 second action time, but wh60-065 protection action current 1.3 amps does not meet the requirements, which should eventually choose to self recovery fuse Wh60075 specifications
We can see from the above example can be seen since the recovery of the selection of the fuse can be based on the top of the 8 steps to carry out the precise scheme of self recovery fuse selection. Specific selection or according to the specific circumstances of the selection after the most experimental test to determine the final right products. Small hope that a lot of the site to learn science and technology extension. Do not know can consult our customer service, explain one by one!