The **WMS2-C3-R/K** is a specialized electronic component, specifically a **Wall-Mounted Smart Sensor** often utilized in HVAC and Building Management Systems (BMS). It is designed to monitor environmental conditions and communicate data back to a central controller. --- ### 1. Technical Specifications The following table outlines the primary electronic and functional characteristics of the WMS2-C3-R/K: | Feature | Specification | | :--- | :--- | | **Sensing Elements** | Temperature (C3 often denotes Triple: Temp, Humidity, CO2) | | **Output Signal** | RS-485 Modbus RTU (Digital) or 0-10V/4-20mA (Analog) | | **Operating Voltage** | 24V AC/DC | | **Mounting Type** | Wall Mount (Indoor) | | **LCD Display** | Included (for real-time value monitoring) | | **Housing Material** | Fire-resistant PC/ABS Plastic | --- ### 2. Key Electronic Components The internal circuitry of this device typically consists of four main subsystems: #### A. Sensing Transducers * **Temperature Sensor:** Usually a high-precision NTC thermistor or a digital CMOS sensor. * **Humidity Sensor:** Capacitive polymer sensor for relative humidity. * **CO2 Module:** (In "C" variants) An NDIR (Non-Dispersive Infrared) sensor for gas concentration measurement. #### B. Signal Processing Unit * An integrated **Microcontroller (MCU)** acts as the brain. It converts the raw analog signals from the sensors into digital values, applies calibration offsets, and manages the display refresh rate. #### C. Communication Interface * **RS-485 Transceiver:** Enables the "R" (Remote/Relay) functionality, allowing the device to talk to a PLC or DDC controller over long distances using the Modbus protocol. * **Relay Outputs:** Potential-free contacts used to trigger external hardware (like fans or dampers) based on setpoint thresholds. #### D. Power Management * Internal **Voltage Regulators** convert the 24V input down to 3.3V or 5V required for the sensitive digital electronics. --- ### 3. Application Use Cases 1. **Demand Controlled Ventilation (DCV):** Using the CO2 sensor to increase fresh air intake only when occupancy is high. 2. **Server Room Monitoring:** Precise temperature and humidity tracking to prevent hardware failure. 3. **Smart Buildings:** Integration with LonWorks or BACnet/Modbus systems for centralized climate control.