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Product name: Inrush Current Limiting NTC Thermistor MF72 series

Item: 13D series

Inrush Current Limiting NTC Thermistor MF72-13D series

Brief Introduction:
MF72 series NTC thermistor devices for limiting surge current are made of a specially formulated metal oxide ceramic material and in the form of radial resin coated that is capable of limiting high surge current. Applying power NTC thermistor in the power supply loop is the most simple, convenient and effective measure to restrain switch-on surge current and protect electronic equipment.

Product Application:
1. Conversion power supply, switch power supply, UPS power
2. Power supply circuit, electronic circuit of equipments
3. Electric heater
4. Electronic ballast
5. Oscillight,display
6. Filament protection of bulb,electronic energy-saving lamps and other lighting lamps

NTC Thermistor Working principle:
When turn on an electrical equipment,a prodigious surge current arises in the moment can be restrained effectively by a power NTC thermistor connected in series with the power circuits,which including a capacity, heater, motor.This inrush current lasts short, but its peak current is prodigious. It can even exceed 100 times of operating current in conversion power, switch power and UPS power.So limiting the surge current measures must be took effectively.When current is applied on NTC thermistor directly, NTC resistance may decrease with the heating of NTC thermistor speedily. Power type NTC thermistor has a specified zero power resistance, when it is in series in the circuit, it can restrain the switch-on surge current effectively. After it completes surge current limiting function, due to the current operation continuously, the resistance can decrease to very small value, its power consumption can be neglected, does not influence the normal operation current. Therefore, applying power NTC thermistor in the power supply loop is a most effectively and most brief measure to restrain surge current,protecting electrical equipment from destruction.
Be noticed, the thermistor can not be used in parallel in the circuit since one unit will tend to conduct all the current available nearly.

Main parameter:
Zero Power Resistance Value R25(Ω)
Maximum stable current I(A)
Approximate resistance in maximum current(Ω)
Thermal time constant(S)
Dissipation factor (mW/ ℃)
Operating temperature range -55~+200 ℃ 

NTC Thermistor Selection Guide:
1.  Maximum operating current > Actual operating current in the power loop
2.  Rated zero power resistance at 25C
of which, E: loop voltage, Im: Surge current
For conversion power, reversion power, switch power, UPS power, Im=100 times operating current
For filament, heater, Im =30 times operating current

1.long service life,high reliability,wide operation range
2.small dimension,large power,strong in inrush current limiting
3.fast response to surge current
4.large material constant,low resistance residue
5.can limit inrush current effectively
6.minimum power loss in stationary state(Normally just 1W or less than 50W power)
7.high thermal and electrical reliability
8.wide selection of electrical characteristics
9.Wide operating temperature -55~+200 ℃
Comparison without and with NTC thermal resistor application

NTC Thermistor Dimension(Unit: mm):

Marking of Part Number:

1.Series:MF72- NTC thermistors series for limiting surge current
2.R25 resistance:10-10Ω
4.Chip diameter:11-Φ11mm

Remarks:Except for the reference size and parameter above,different electrical parameter and encapsulation mode can be custom made per client's requirement.
You can send us required specifications to info@dxmht.com or provide reference samples to our factory office:
        Attention:Ivan Wong
And then samples&orders can be custom made per your requirement.