Product Description
The WMZ12A is a positive temperature coefficient (PTC) thermistor made of semiconductor ceramic material. Its core characteristic is that its resistance exhibits a nonlinear, sharp increase with increasing temperature. This series of thermistor typically features radial leads and an epoxy resin encapsulation, offering advantages such as compact size, rugged construction, easy installation, and high reliability. Primarily used as a self-resetting overcurrent protection component, it is widely used in various electronic circuits, power supplies, and motor windings, providing safe and reliable overload and overheating protection.
Specification
Product Name: PTC Thermistor
R25 : 10-2200Ω±30%
Curie Temperature : 50-120℃
Diameter : 4.5-24mm
Application : Overcurrent protection of the Ballast /CFL/Adaptor /Charger
Color : Green
Features
Self-reset protection: When an overcurrent fault occurs in a circuit, the WMZ12A quickly enters a high-resistance state (commonly known as "tripping") due to heat generated by the current, significantly limiting the circuit current and providing protection. Once the fault is eliminated and the power is turned off and the device cools down, its resistance automatically returns to a low-resistance state, eliminating the need for manual replacement and significantly improving maintenance convenience.
Fast response: In the event of a sudden overcurrent event, the WMZ12A reacts and limits the current in an extremely short time (milliseconds), effectively preventing the fault from escalating and protecting subsequent precision components.
High reliability and long life: Due to its solid-state ceramic element and lack of mechanical moving parts, it is shock- and vibration-resistant, offering extremely long life and stable performance under normal operating conditions.
Various rated parameters available: The WMZ12A series is typically offered in a variety of rated zero-power resistance values, holding current (Ihold), and trip current (Itrip), allowing engineers to flexibly select the device based on their specific circuit design requirements.
Excellent environmental adaptability: The epoxy resin encapsulation provides excellent insulation and moisture and dust resistance, ensuring stable operation in a variety of harsh environments.
Application
Overcurrent Protection:
Power Circuit: Installed at the input or output of switching power supplies, adapters, and chargers as primary or secondary overcurrent protection.
Electronic Devices: Used to protect speakers, motor driver boards, displays, etc. from short circuit or overload damage.
Battery Pack: Used in series in rechargeable battery packs to prevent overheating and potential danger from external short circuits or overcharging.
Motor Protection:
Directly embedded or attached to the windings of AC/DC motors (such as refrigerator compressors, fan motors, and water pump motors), when the winding temperature rises abnormally due to motor stalling, excessive load, or other factors, the PTC activates and disconnects the control circuit, providing overheat protection.
Degaussing Circuit:
This was once a core component of the degaussing coil in CRT televisions and monitors. At the moment of power-on, its low resistance in the cold state allows a large current to flow, generating a strong alternating magnetic field for demagnetization. Subsequently, due to its own heat resistance increasing, the current automatically decreases to a maintenance level.
Temperature Sensing and Compensation:
Leveraging its resistance's sensitivity to temperature, it can be used as a simple temperature sensor or for temperature compensation of other components in a circuit.
