ITEM NAME:Modbus RTU 2 Way Relay Module Output 2 Channel Switch RS485 TTL 12V Input A#S Product Description Description: Specification: Power Source: DC Contact Load: Low Power Voltage: 12V Color: blue Material: metal + plastic Package size: 115mm*75mm*15mm/4.52*2.95*0.59'' Package weight :43g Hardware Resources: RS485 communication interface TTL communication interface 2 optocoupler isolation input 2 way optocoupler isolation output A user button A user LED A power indicator A STM32F030F4 microcontroller 2 relay status indicators LED lights Power supply terminal interface (12V power supply) Modbus RTU instruction Baud rate: 9600 8 NONE 1 Hexadecimal send Hexadecimal reception Steps: 1. Software settings communication baud rate 2. Set the address (communication using the device address, the default address is 01) Note: Please allow 1-3mm differs due to manual measurement. Due to the different display and different light, the picture may not show the actual color of the item. Thanks for your understanding. Included: 1 X Modbus RTU 2 Way Relay Module.Modbus RTU instruction. Included: 1 X Modbus RTU 2 Way Relay Module. RS485 communication interface. TTL communication interface. 2 relay status indicators LED lights. A power indicator. 2 way optocoupler isolation output.