The part number **3-R27K** typically refers to a specific type of electronic component, most commonly identified as a **Metal Oxide Varistor (MOV)** or a high-precision **Resistor**, depending on the manufacturer's prefixing system. Based on standard electronic component coding, here is the breakdown of its characteristics: ### 1. Component Identification In most industrial contexts, this part is a **Metal Oxide Varistor** (often from manufacturers like BrightKing or Thinking Electronic). | Specification | Details | | :--- | :--- | | **Component Type** | Metal Oxide Varistor (MOV) | | **Nominal Voltage** | 27V | | **Tolerance** | ±10% (Indicated by 'K') | | **Diameter/Size** | 3mm (Indicated by '3') | --- ### 2. Technical Breakdown of the Code The alphanumeric string "3-R27K" can be deciphered as follows: * **3**: Represents the **Disk Diameter**. In this case, it is a small-form-factor component with a 3mm diameter, suitable for compact circuit boards. * **R**: Often acts as a decimal point or a series identifier for **Voltage**. * **27**: The **Varistor Voltage**. This component is designed to trigger or become conductive when the voltage reaches approximately 27 volts. * **K**: The **Tolerance code**. In the electronics industry, 'K' stands for **±10%**. --- ### 3. Function and Applications The primary purpose of a 27V Varistor is **Overvoltage Protection**. #### How it works: * **Normal State:** The component has high resistance and acts as an open circuit. * **Surge State:** When a voltage spike exceeds 27V, the resistance drops instantly, shunting the excess current to the ground and protecting sensitive downstream components. #### Common Uses: 1. **Low Voltage DC Lines:** Protecting sensors or communication ports. 2. **Automotive Electronics:** Safeguarding 12V systems from "load dump" spikes. 3. **Handheld Devices:** Protecting internal circuitry from Electrostatic Discharge (ESD). --- ### 4. Alternative Interpretation (Resistor) If the part is a **Resistor** rather than a Varistor: * **Value:** 0.27 Ohms (if R is a decimal) or 27k Ohms (if K is a multiplier). * **Precision:** 10% tolerance. * *Note: Given the "3-" prefix, it is significantly more likely to be a Varistor or a specific Thermistor.* ---