ptc thermistor for circuit protection,lightning protection of telecom terminal interface mz2 series-九游会下载

brief introduction of ptc thermistor for circuit protection of telecom apparatus:

a ptc thermistor for heat protection,overvoltage protection and lightning strike prevention,mz24-9r0m160, 

which could withstand a high voltage of 600v and effectively prevent telecom terminal telephone unit interface 

from damage caused by overcurrent and overheat or lightning strike. this thermistor has been widely recognized 

and applied by many manufacturers of telecom equipments. 

product application of ptc thermistor for circuit protection of telecom apparatus:

1.telecom terminal telephone unit interface

2.telecom equipments

working principle of ptc thermistor for circuit protection of telecom apparatus:

to provide good protection under such conditions a ptc thermistor is connnected in series with eachline.usually as 

secondary protection;however,even with primary line protection(usually a gas discharge tube),the ptc thermistor 

must fulfill severe requirements.surge pulses of up to 2 kv can occur and in order to withstand short-term power 

induction the ptc thermistor withstand high voltage.if the line has primary circuit protection,a 220v to 300v ptc thermistor 

is adequate.without primary circuit protection,600v ptc thermistor is necessary.

the restricting overload protection ptc thermistor is connected in series in the overload circuit. when the circuit is 

in the normal working state , the current flowing through the ptc thermistor is not high enough to make the temperature 

exceed the curie temperature for protection ,and the ptc thermistor is always in the low resistance state. when the circuit 

breaks down and the circuit current increases a lot, the resistance of restricting overload protection ptc thermistor heating 

sharply until the circuit is "cut off" relatively to achieve circuit protection purpose. after clearing the circuit trouble, 

the ptc thermistor begins to cool and come back to the state of low resistance, and then the circuit enters normal working 

condition. when the circuit breaks down next time, the ptc thermistor can enter the state of circuit protection again.

advantages:

1. automatic circuit protection,can resume steadily;do not need to be reset after circuit protection

2. contactless,noiseless and flameless;

3. reacts fast;

4. with a better performance of overvoltage protection,can operate in 110/230v ac (high resistance state) continuously

5. low rated current

6. small steady resistance;

7. narrow resistance tolerance (resistance matching) 

8. satisfy itu-t k20 k21 requirement. 

--surge current（10/700μs） 

--induction voltage（600v,1a,0.2s） 

--power line contact（230v,15min.） 

9.long stability 

10.rohs compliant 

dimension(unit: mm):

marking of part number:

1.series:ptc thermistor for circuit protection,overvoltage protection of telecom apparatus;

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

3.r25 resistance:55r-55;

4.resistance tolerance:m /-20%;

5.non trip current(25 ℃):070-70ma;

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

7.max. voltage:250-250v.

specifications and part no.: