The **M2RS-0B-R/UL** is a high-performance, compact **Rotary Coded Switch** manufactured by **Copal Electronics** (now Nidec Components). It is specifically designed for binary-coded settings in space-constrained industrial and consumer electronics. --- ### 1. Key Technical Specifications The following table outlines the core electronic and mechanical parameters of the M2RS series: | Parameter | Specification | | :--- | :--- | | **Code Type** | Real Code (Binary Coded Decimal/Hexadecimal) | | **Number of Positions** | 10 Positions (0-9) | | **Actuator Style** | Shaft (Knob) type | | **Mounting Type** | Through-hole (PC Pin) | | **Contact Rating (Switching)** | 100mA at 5V DC | | **Contact Rating (Non-Switching)** | 100mA at 50V DC | | **Contact Resistance** | 100 mΩ maximum | | **Operating Temperature** | -25°C to +70°C | | **UL Rating** | UL94V-0 (Self-extinguishing plastic) | --- ### 2. Functional Description The M2RS-0B-R/UL acts as a digital input device. By rotating the shaft, the internal contacts bridge specific output pins to a common pin (COM), creating a **binary code** output. * **Binary Coded Decimal (BCD):** Since this is a 10-position model, it provides outputs representing numbers 0 through 9 in 4-bit binary. * **Sealing:** These switches are usually "washable," meaning they are sealed with an O-ring to prevent flux or cleaning fluids from entering the contacts during the soldering process. * **R/UL Suffix:** Indicates the part meets specific Underwriters Laboratories (UL) safety standards and is compliant with RoHS environmental regulations. --- ### 3. Pin Configuration (Typical) While you should always consult the official datasheet for the specific PCB footprint, the 4-bit BCD output generally follows this logic: | Position | Pin 1 (2^0) | Pin 2 (2^1) | Pin 4 (2^2) | Pin 8 (2^3) | | :--- | :--- | :--- | :--- | :--- | | **0** | Open | Open | Open | Open | | **1** | Closed | Open | Open | Open | | **5** | Closed | Open | Closed | Open | | **9** | Closed | Open | Open | Closed | --- ### 4. Common Applications * **Address Setting:** Used on networked devices (like RS-485 or CAN bus nodes) to manually set a unique ID. * **Mode Selection:** Selecting operational modes on industrial control panels. * **Configuration:** Adjusting internal parameters on a PCB without needing a digital interface or display.