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Product name:Overcurrent protection and lightning strike prevention PTC thermistor for telecom terminal telephone unit interface

Item:MZ2 series

Overcurrent&overheat protection and lightning strike prevention PTC thermistor for telecom terminal telephone unit interface-MZ2 series

Brief Introduction:
A PTC thermistor for overcurrent&overheat 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&overheat or lightning strike. This device has been widely recognized and applied by many manufacturers of telecom equipments.

Product Application:

1.Telecom terminal telephone unit interface
2.Telecom equipments
Working principle:
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 protection,a 220V to 300V PTC thermistor is adequate.Without primary protection,600V PTC device is necessary.The restricting overloading protection PTC Thermistor is connected in series in the overloading 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 PTCR is always in the low resistance state. When the circuit breaks down and the circuit current increases a lot, the resistance of restricting overloading protection PTC Thermistor heating sharply until the circuit is "cut off" relatively to achieve 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 protection again.

1. Automatic protection,can resume steadily;do not need to be reset after protection
2. Contactless,noiseless and flameless;
3. Reacts fast;
4. With a better performance of withstanding voltage,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

Marking of Part Number:

1.Series:PTCR for overcurrent and overload 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.
Dimension(Unit: mm):

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:
And then samples&orders can be custom made per your requirement.