The **M2RT-12-R/K** is a specific model within the **M2RT series**, which are high-performance, compact **Rotary Switches** (often referred to as sub-miniature rotary switches). These are commonly used in industrial controls, medical equipment, and telecommunications. ### 1. Key Technical Specifications Based on the part number nomenclature, here are the primary electronic and mechanical characteristics: | Property | Specification | | :--- | :--- | | **Switch Type** | Rotary Switch | | **Number of Poles** | 1 Pole | | **Number of Positions** | 2 to 12 Positions (Adjustable) | | **Voltage Rating** | 125V AC / 28V DC (Typical) | | **Current Rating** | 150mA to 250mA (varies by load type) | | **Contact Resistance** | < 20 mΩ | | **Dielectric Strength** | 500V AC for 1 minute | | **Mechanical Life** | 10,000 cycles minimum | --- ### 2. Part Number Breakdown The suffix and prefix provide details on the mounting and contact material: * **M2RT**: Series identifier (Sub-miniature rotary). * **12**: Maximum number of positions available on the wafer. * **R**: Typically denotes **Right Angle** PC terminals (mounting orientation). * **K**: Often refers to the **Knob** or **Actuator** style (e.g., a knurled shaft or a specific keyed shaft). --- ### 3. Electronic Components & Materials The internal construction of the M2RT-12-R/K relies on several high-grade materials to ensure signal integrity: 1. **Contacts**: Usually **Gold-plated** or **Silver-plated** brass/copper alloy. Gold is preferred for low-level switching to prevent oxidation. 2. **Housing/Insulator**: High-temperature **Diallyl Phthalate (DAP)** or similar thermoset plastic, providing high insulation resistance. 3. **Indexing Mechanism**: A ball-and-spring detent mechanism that provides the "click" feel and ensures the switch stays in the selected circuit position. 4. **Terminals**: PC pins designed for direct soldering onto a Printed Circuit Board (PCB). --- ### 4. Circuit Diagram Representation A 1-pole, 12-position rotary switch operates as a "Single Pole, Multi-Throw" (SP12T) switch. ```mermaid graph LR Common((Common Pin)) --- S[Switch Arm] S --> P1(Pos 1) S --> P2(Pos 2) S --> P12(Pos 12) ``` --- ### 5. Common Applications * **Test Equipment**: Selecting between different measurement ranges (Volts, Amps, Ohms). * **Audio Equipment**: Input source selection or gain stepping. * **Industrial Panels**: Mode selection (Manual, Auto, Off).