The **SED-A13-R** is an electronic module primarily used as a **wireless door/window contact sensor** or a **multifunctional digital input sensor** within the Smart Energy or Building Automation sectors. It is commonly associated with the Schneider Electric (SE) or Viconics product lines, specifically designed for Zigbee networking environments. --- ### Core Specifications & Parts | Feature | Description | | :--- | :--- | | **Communication Protocol** | Zigbee Pro (2.4 GHz) | | **Power Source** | 2x AAA Alkaline Batteries (3V DC) | | **Inputs** | Internal Reed Switch + External Dry Contact Input | | **Mounting** | Surface mount (screws or adhesive) | | **Compatibility** | VT8000 series Room Controllers / MPM Gateways | --- ### Key Electronic Components #### 1. Wireless Transceiver (Zigbee) The heart of the device is a low-power Zigbee radio module. It operates on the IEEE 802.15.4 standard, allowing it to join mesh networks. This chip handles encryption (AES-128) and communicates state changes to a central gateway or room controller. #### 2. Reed Switch (Magnetic Sensor) The unit contains an internal **magnetic reed switch**. When a magnet (placed on a door or window) is brought close to this component, the circuit closes. When the magnet moves away, the circuit opens, triggering a wireless "State Change" signal. #### 3. Terminal Block (Digital Input) One of the unique electronic parts of the SED-A13-R is its internal terminal block. This allows it to act as a **wireless bridge** for other non-wireless devices: * **Dry Contact Input:** You can wire a third-party sensor (like a water leak detector or a manual switch) into this terminal. * **Function:** It converts a physical wired signal into a Zigbee wireless signal. #### 4. Power Management Circuitry Designed for ultra-low power consumption, the electronic board includes: * **Sleep Mode Controller:** Keeps the radio in a low-power state, "waking up" only when a sensor event occurs or for periodic heartbeat check-ins. * **Battery Voltage Monitor:** Reports battery levels back to the head-end system to alert maintenance when the AAA batteries are low. --- ### Use Cases in Building Automation 1. **HVAC Interlock:** When a window is opened, the SED-A13-R sends a signal to the VT8000 thermostat to shut off the AC to save energy. 2. **Occupancy Detection:** Can be used on bathroom doors to help determine if a room is occupied based on door transitions. 3. **Security/Monitoring:** Monitoring access to restricted cabinets or equipment rooms using the external input.