The term **R-FWE-R** typically refers to a specific naming convention or part number suffix found in electronics, most notably associated with **Thermal Cutoffs (TCO)** or **Thermal Fuses**, such as those manufactured by companies like *AUPO* or *NEC/SCHOTT*. Below is a breakdown of the electronic components and technical specifications associated with this classification. --- ### 1. Component Overview These parts are safety devices designed to break an electrical circuit when the operating temperature exceeds a specific rated limit. Unlike a circuit breaker, a thermal fuse is a **one-time use** component and must be replaced once it "blows." | Feature | Description | | :--- | :--- | | **Component Type** | Thermal Cutoff (TCO) / Thermal Fuse | | **Reset Type** | Non-Resettable (Single use) | | **Key Function** | Overheat protection for appliances and industrial equipment | | **Mounting** | Through-hole (Axial leads) | --- ### 2. Technical Specifications The "R-FWE-R" designation usually implies specific environmental compliance (like RoHS) and structural builds (like lead-free terminals). * **Rated Functioning Temperature ($T_f$):** This varies by specific model number, but they generally range from $70^\circ C$ to $250^\circ C$. * **Voltage Rating:** Commonly rated for **250V AC**. * **Current Rating:** Typically available in **10A** or **15A** configurations. * **Case Material:** Ceramic or metal body with an organic thermal pellet inside. --- ### 3. Deciphering the Part Structure While manufacturers vary, the suffix elements usually represent the following: | Code Segment | Meaning | | :--- | :--- | | **R** | Often denotes **RoHS Compliance** (Restriction of Hazardous Substances). | | **FWE** | Typically refers to the **Lead-Free** (Pb-free) finish on the wires/terminals. | | **R** | Can indicate **Taped/Reel** packaging or a specific tolerance rating. | --- ### 4. Working Principle The internal mechanism is straightforward but highly reliable: 1. **Normal State:** The internal thermal pellet is solid, holding a spring-loaded contact in place, allowing current to flow. 2. **Overheat State:** When the ambient temperature reaches the $T_f$ rating, the pellet melts. 3. **Circuit Break:** The compressed spring pushes the contacts apart, permanently opening the circuit and stopping the flow of electricity to prevent a fire. --- ### 5. Common Applications * **Household Appliances:** Coffee makers, irons, hair dryers, and rice cookers. * **HVAC:** Electric heaters and air conditioner motors. * **Automotive:** Seat heaters and cooling fan motors. * **Power Supplies:** Transformers and battery chargers. ---