The **W2PA-5BZ-R/N** is a specialized high-power wire-wound resistor designed for power supply circuits, industrial electronics, and surge protection. It is manufactured by **TA-I Technology**. --- ### 1. Component Overview The "W2P" series indicates a **Wire-Wound Flame-proof Power Resistor**. These components are designed to dissipate heat efficiently while maintaining stable resistance values under high-load conditions. | Feature | Specification | | :--- | :--- | | **Component Type** | Wire-wound Resistor | | **Power Rating** | 2 Watts (2W) | | **Tolerance** | ±5% (indicated by 'J' or '5') | | **Coating** | Flame-proof Silicone | | **Lead Style** | Axial Lead (Standard) | --- ### 2. Part Number Breakdown The nomenclature for this series follows a specific logic: | Code Segment | Meaning | Description | | :--- | :--- | :--- | | **W2P** | Series | Wire-wound Power Type | | **A** | Lead Forming | Axial Lead (Standard straight) | | **5B** | Power Rating | 2 Watts (Size Code 5B) | | **Z** | Temperature Coeff. | Standard Temperature Coefficient | | **R/N** | Resistance | Denotes the Ohm value (e.g., "R" for decimal) | --- ### 3. Technical Characteristics #### A. Wire-Wound Construction Unlike carbon film resistors, these are made by winding a resistive wire (often Nichrome) around a ceramic core. This makes them: * **Inductive:** Not suitable for high-frequency switching. * **Surge Resistant:** They can handle high momentary voltage spikes much better than film resistors. #### B. Flame-proof Protection The "P" in the series name signifies that the coating is made of a non-flammable material. In the event of an overload, the resistor will open up (like a fuse) without catching fire or emitting smoke that could damage surrounding components. #### C. Thermal Stability The ceramic core provides excellent heat dissipation, allowing the component to operate at high temperatures (often up to 155°C or 200°C depending on the specific derating curve). --- ### 4. Typical Applications 1. **Inrush Current Limiting:** Used in power supplies to prevent a massive surge when the device is first turned on. 2. **Voltage Dividers:** In high-power circuits where precision is less critical than power handling. 3. **Snubber Circuits:** Used to suppress voltage transients in motor control or relay circuits. 4. **Discharge Resistors:** To safely drain high-voltage capacitors after power is disconnected. ---