ntc thermistor for surge suppression-九游会下载

model number:

mf72 d5 series

mf72 d8 series

mf72 d10 series

mf72 d13 series

mf72 d15 series

mf72 d20 series

etc.

product coating color: black or green

brief introduction of ntc thermistor for surge suppression:

mf72 series power type ntc thermistor for surge suppression 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 of ntc thermistor for surge suppression:

1. conversion power supply, switch power supply, ups power

2. power supply circuit, electronic circuit of electric equipments

3. electric heater

4. electronic ballast

5. oscillight,display

6. filament protection of bulb,electronic energy-saving lamps and other lighting lamps

application example of ntc thermistor for surge suppression:

working principle of ntc thermistor for surge suppression:

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 thermistor 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 ntc thermistor can not be used in parallel in the circuit since one unit will tend to conduct all the current available nearly.therefore,thermistor may be used in the ac(position a1 or a2) or the dc(position d1 or d2) locations in the circuit(see fig a).

main parameter of ntc thermistor for surge suppression:

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 ℃  

selection guide of ntc thermistor for surge suppression:

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 

advantages of ntc thermistor for surge suppression:

1.long service life,high reliability,wide operation range

2.small dimension,large power,strong in surge protection

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 ℃  

10,rohs compliant 

comparison without and with ntc thermistor application 

dimension(unit: mm):

marking of part number: 

marking of part number 

1.series:mf72- ntc thermistor for surge suppression

2.r25 resistance:10-10ω 

3.dimension:d-diameter

4.chip diameter:11-φ11mm

specifications and part no.: