ptc thermistor for overload protection mz31 series-九游会下载

brief introduction:

mz31 series ptc thermistor is a million- time safety thermistor of automatic circuit protection,recoverability, using repeatedly, and no trigger, 

noise or protective component that could protect and restore from abnormal temperature and current automatically,which called "auto restore fuse" 

and "ten-thousand-time fuse".recoverability, using repeatedly, and no trigger, noise or sparks. 

working principle:

as indicated in fig 2 as below,when circuit is in the normal state, the current through ptc thermistor is lower than the rated current and ptc thermistor

is in the normal state with small resistance value,which will not affect the normal operation of the protected circuit such as primary and secondary loops 

of the voltage transformer.in case of some trouble in the circuit and the current is bigger than the rated current,the ptc thermistor will become hot 

quicklyand present high resistance value, which sets the circuit relatively “off” to protect the circuit from damage.after the trouble is removed,ptc thermistor

will automatically restore its low resistance state and the circuit will resume normal operation.

product applications:

circuit protection,overvoltage protection,overload protection,short circuit protection of general circuit,e.g. transformers,mico motor,switch power,

electric energy meter,charger,adaptor,meter,apparatus,electronic coils,control panels,home appliances,air conditioning,microwave oven etc. 

overload protection of intelligent watt-hour meter rs485 interface, digital multimeter,micromotor and transistor.

advantages:

1.automatic circuit protection,can resume steadily, 

2.contactless,noiseless and flameless,

3.reacts fast,

4. with a better performance of overvoltage protection,

5.wide operating voltage range,

6.small steady resistance,

7.low rated current,

8.small resistance,small size,

9.stable for a long time, 

10.no need to be reset supply after overload protection,

11.wide operating temperature range,

0 ~ 60°c (v=vmax), 

-25 ~ 125°c (v=0), 

12.rohs compliant. 

choose guidelines of ptc thermistor for overvoltage protection:

in selecting ptc thermistor as overvoltage protection,overload protection component,firstly,make sure of the maximum operating current in the 

circuit(non-trip current of ptc thermistor) and maximum operating voltage,rated zero power resistance,and also the outlook and dimension should 

be also taken into consideration.relation between operating temperature,operating current and non-operating current is as shown in fig 3 as below.

operating current is normally 2-3 times compared as non-operating current,and both of the currents will be reduced as operating temperature increases.

marking of part number:

1.series:ptc thermistor for overvoltage protection

2.type:1-disc,2-encased,3-pin form-coating,4-pin form non-coating,5-smd

3.type:a-general, b-compount, c-moduie

4.chip size: 8-φ8mm          9-φ9mm         11-φ11mm      

5.curie temperature: f-50℃       h-75℃       n-100℃   p-120℃     k-125℃

6.r25 resistance: 6r0-6ω     6r5-6.5ω      70r-70ω      121-120ω 

7.resistance tolerance: k /-10%        m /-20%         h /-25%         n /-30%

8.greatly voltage:250-250v         265-265v

9.wire shape: s-straight, a-axis formed, u-in-formed

dimension(unit: mm):

specification&part no.: