How do you select NTC thermistors for inrush current limiting?
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How do you select NTC thermistors for inrush current limiting?
There are 3 major criteria for selecting the best NTC Thermistor inrush current limiter, surge suppressor for an application:
- Rated resistance (R25)
- Maximum permissible continuous current under rated operating conditions (Imax, DC or RMS values for AC)
- Maximum capacitance CT to be switched.
How do you create inrush current limiter?
There are two ways to design inrush current limiter using the resistor limit method. The first one is to add a series resistor to reduce the current flow in the circuit line and the other one is to use line filter impedance in AC supply input.
What is NTC capacitor?
NTC thermistors are temperature-dependent resistors that employ special semiconductor ceramics with a negative temperature coefficient (NTC). NTC thermistors used as current protection devices are also called power thermistors. A fixed resistance or an NTC thermistor can be used to limit inrush currents.
Which is used as a inrush current limiter?
thermistors
Negative temperature coefficient (NTC) thermistors and fixed resistors are often used to limit inrush current. NTC thermistors can be used as inrush-current limiting devices in power supply circuits when added in series with the circuit being protected.
How is NTC calculated?
The actual resistance values of a particular NTC thermistor are obtained by multiplying the ratio RT/R25 (tabulated value) by the resistance value at 25 °C (specified in the data sheets).
How does a NTC thermistor work?
With an NTC thermistor, when the temperature increases, resistance decreases. Conversely, when temperature decreases, resistance increases. When temperature increases, the resistance increases, and when temperature decreases, resistance decreases. This type of thermistor is generally used as a fuse.
What is a 10K thermistor?
The enclosed negative temperature coefficient (NTC) thermistor, p/n 1600-10K, works by translating temperature into resistance, with resistance decreasing as temperature increases (hence the ‘negative coefficient’).