1. Mature and stable 8-bit MCU on board: and MAX485 level conversion chip 2. Communication protocol: Supports standard Modbus RTU protocol 3. Communication interface: Supports RS485/TTL UART interface 4. Communication baud rate: 4800/9600/19200, default 9600bps, supports power-off saving 5. Optocoupler input signal range: DC3.3-30V (this input cannot be used for relay control) Output signal: Relay switch signal, supporting manual, flash close, and flash break modes. The delay base for flash close/flash break is 0.1s, and the maximum set flash close/flash break time is 0 XFFFF x 0.1S=65535 x 0.1s=6553.5s Device address: Range 1-255, default 255, supports power-off saving Board 1 circuit 5V, 10A/250V AC 10A/30V DC relay, capable of continuously attracting 100000 times with diode surge protection and short response time On board relay switch indicator light Power supply voltage: DC7-24V, with input anti reverse connection protection Due to different batches, there may be differences in product appearance and printed text, which will not affect use. Colour:As Shown Material:PCB Package Contents: 2 x Relay Modul Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.