The definition of thermal time constant for an inrush current limiter is the time required for it to change 63.2% of the total difference between its initial temperature and final temperature when subjected to a step function change in temperature. In other words, the time that it takes our Inrush Current Limiter to recover to 50% of its initial resistance is called the Thermal Time Constant. This data can be found on all of the data sheets on our website. The thermal time constant is different for all of the inrush current limiters based on their mass. If your application needs to be turned on and off repeatedly and you need to stop the inrush of current, then this circuit should work for you:

NTC Thermistor Thermal Time Constant

You need to choose the correct relay for your application to use with the inrush current limiter. The timer is half a cycle or 10 milliseconds here. You might want a longer timer if needed. This circuit allows the inrush current limiter to drop the inrush and then it is completely taken out of the circuit. Thus, it will take very little time to cool down.


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