MF72 Series 2.5D-11 2.5 Ohm 11mm Surge Current Suppression NTC Thermistor For Power Adapter

Specifications:

Main technical parameters:

Note: Multiple resistance values ​​and pin types can be customized on demand.

What is an inrush current suppression power type NTC thermistor

A power NTC thermistor can be a cost-effective device for limiting the amount of inrush current in a switching power supply or other equipment when power is first applied. A power NTC thermistor limits inrush current by acting as a power resistor that drops from a high cold resistance to a low hot resistance when heated by the current flowing through it.

The inrush current limiter supplies the NTC thermistor protection circuit with unnecessarily high current, suppressing high inrush current surges while its resistance remains negligible during continuous operation. Due to its low resistance in the operating state, power thermistors dissipate much less power than fixed resistors commonly used in this application.

Application of Inrush Current Suppression Power Type NTC Thermistor

Limiting inrush current, suitable for protection of switching power supplies, UPS power supplies, transformers, motors, various electric heating appliances, energy-saving lamps, ballasts, various power circuits, amplifiers, color displays, monitors, color TVs, filament protection, etc.

Power thermistor elements can also be used for soft starting of motors, for example, in vacuum cleaners with a continuous current of up to 20 A.

Inrush current suppression power type NTC thermistor advantages:

· Low-cost solid-state device for suppressing inrush current.

· Minimizes line current distortion and radio noise.

· Protects switches, rectifier diodes and smoothing capacitors from premature failure.

· Prevents false fuse blowing.

Inrush current suppression power type NTC thermistor features:

· Resin coated disc thermistor with non-insulated leads.

· Suitable for AC and DC circuits up to 265 V (rms).

· Wide range of resistances, currents and sizes.

· Excellent mechanical strength.

· Suitable for PCB mounting.

Several factors to consider when selecting an inrush current suppression power NTC thermistor

1) Maximum operating current > actual operating current in the power circuit

2) At 25°CRated zero power resistance, E: loop voltage, Im: surge current

For conversion power, recovery power, switching power, UPS power, Im = 100 times the operating current For filaments, heaters, Im = 30 times the operating current

3) The larger the B value, the smaller the residual resistance and the lower the operating temperature.

4) Generally speaking, the larger the time constant and dissipation coefficient, the larger the NTC thermal capacity, and the stronger the surge current suppression capability of the NTC thermistor.

Inrush Current Suppression Power Type NTC Thermistor Application Notes

1) For inrush current limiting, the NTC thermistor must be connected in series with the load circuit. Several inrush current limiters can also be connected in series for higher damping. Inrush current limiters must not be connected in parallel.

2) Generally, inrush current limiters need time to return to a cold state, where they can provide adequate inrush current limiting due to their high resistance. The cooling time depends on the ambient conditions.

3) It should be taken into account that the surrounding area of ​​the NTC thermistor may become hot. Make sure that adjacent components are kept at a sufficient distance from the thermistor to ensure a proper cooling time for the thermistor.

4) Make sure that the design operating temperature of the adjacent materials is comparable to the surface temperature of the thermistor. Make sure that the surrounding components and materials can withstand this temperature.

5) Ensure that the thermistor is adequately ventilated to avoid overheating.

6) Avoid contamination of the thermistor surface.

7) Avoid contact of the NTC thermistor with any liquids and solvents. M