RS485 Wireless Modem 433MHz 20dBm

Physical dimensions: 74 mm × 24 mm × 16 mm (excluding antenna); operating voltage: 4.5–5.5 V DC; RS485 interface pinout: 5V, GND, A+, B−. Frequency range: 433–458.5 MHz, supporting 255 distinct channels. Transmit power: adjustable from −40 dBm to +20 dBm (100 mW max) in 10 steps. Receiver sensitivity: −114 dBm. Serial interface supports 1200–19200 bps (9600 bps default); air data rate: 10–100 kbps. Line-of-sight wireless distance: up to 500 m. Operating ambient temperature: −25 °C to +75 °C. Construction: blue-coloured plastic and metal enclosure. Supplied as a matched pair (2 pcs), each fully assembled and tested. Functions as a wireless RS485 repeater/buffer: data sent on one module’s serial port appears identically on the other’s — preserving timing and framing. Supports 2-device direct link or ≥3-device bus emulation (one master, multiple slaves), with strict turn-taking enforced to prevent data collisions. Internal microcontroller manages serial buffering (31-byte packets), auto-rate sync between UART and RF layers, and ID-based routing. Deployed across diverse UK/EU applications: controlling IP PTZ security cameras over large estates; reading Modbus-enabled temperature and environmental sensors in HVAC ducts or cold storage; driving addressable LED strips in retail displays; switching RS485 relays (R4D3C32, N4D8B08, N4D8C12); enabling remote meter reading; integrating with Wiser Home or similar KNX/Modbus-compatible platforms; managing access control panels; and feeding data into smart grid metering systems.