Using the following methods can help you select the suitable JKPPTC resettable fuses:

1. List the average working current (I) and voltage (V.) of the circuit.
2. Select the JK PPTC series according to the I, V , product’s type and the form of installation.
3. If the inner temperature of device is over 25°C, the current through the JKPPTC element will increase along with the temperature rise. The holding current can calculate as follows according to discount rate:
   TH=operating current (I) ÷ discount rate of ambient temperature and current value.
4. According to the JJPPTC series ,which selected in step 2 and the IH calculated in step 3,choose the proper element in the catalogue,the IH of the selected JKPPTC must be equal or greater than the IH calculated in step 3.
   If there is any demand for room temperature resistance and the operation time of overcurrent protection on the line use the above method to select relevant series.
   * If you need some special products and can’t find the relevant element in our products table, please contact us, we will make a free special development for your need.