RS485 433MHz 20dBm Wireless Transceiver

Compact unit measuring 74 × 24 × 16 mm (no antenna included); powered by 4.5–5.5 V DC supply. Physical interface: standard RS485 differential pair (A+, B−), plus 5 V power and GND — compatible with common industrial RS485 transceivers and PLC serial ports. Tuned for 433 MHz ISM band (433–458.5 MHz), supporting 255 distinct channels to minimise interference in multi-network sites. Output power spans −40 dBm to +20 dBm (100 mW), settable in 10 calibrated steps. Sensitivity of −114 dBm ensures strong signal capture at edge-of-range. Air data throughput adjusts from 10 kbps to 100 kbps — matched precisely to configured UART speed (1200 / 2400 / 4800 / 9600 / 19200 bps). Each transmitted frame carries up to 31 bytes of application data. Internal microcontroller manages serial framing, channel selection, and power state. AT command interface accessible only during first 180 seconds post-power-up (AT+ENABLE=1 activates it); afterwards, module runs exclusively in transparent mode — AT strings become payload. Rated for continuous operation from −25 °C to +75 °C. Enclosure combines impact-resistant plastic with conductive metal elements for EMI suppression. Two-unit setup enables immediate wireless RS485 link — no configuration needed beyond matching channel and power settings. With three or more units, assign one as master (ID = 0x00) and others as slaves (IDs 0x01–0xFF); master initiates polls or broadcasts, slaves reply individually — emulating classic RS485 multidrop topology with hardware-level timing integrity. Field-proven in diverse applications: wireless control of IP PTZ security cameras across large premises; distributed monitoring of Modbus-connected temperature, pressure, and CO₂ sensors in HVAC systems; wireless dimming and colour control for architectural LED installations; remote switching of RS485-controlled relays in solar inverters or pump stations; telemetry from water/gas/electricity meters in multi-dwelling units; centralised home automation hubs communicating with thermostats, blinds, and door locks; wireless access control readers linked to main panel; and certified smart meter communication modules meeting UK SMETS2 interoperability expectations.