This is an industrial 8-channel Relay module  -8 input - 4 ADC - controlled via RS485 bus, utilizing Modbus RTU protocol. It features embedded protection circuits such as power isolation  TVS diode, etc. It also comes with an DIN Rail Mount enclosure.
 
Features
Configurable device address (1~255), multi devices can be cascaded on RS485 bus
Features flash-on, flash-off function, by passing argument to the command, it is possible to turn on the relay for a while and then close it automatically
Onboard unibody power supply isolation, provides stable isolated voltage, needs no extra power supply for the isolated terminal
Onboard unibody ADI magnetical isolation, allows signal isolation, high reliability, strong anti-interference, low power consumption
Onboard TVS (Transient Voltage Suppressor), effectively suppress surge voltage and transient spike voltage in the circuit, lightningproof & anti-electrostatic
Onboard Optocoupler isolation, prevent interference from external high-voltage circuit connected to the relay
Reverse-proof circuit, prevent the circuit from being damaged accidentally by incorrect connection
High quality relay, contact rating: ≤10A 250VAC/30VDC
Rail-mounted enclosure, easy to install, safe to use
3 LEDs for indicating the MCU status and signal transceiving status
 
Specifications
Power supply voltage: 12V
Communication interface: RS485
Baudrate:  9600
Default communication format: 9600, N, 8, 1
Relay channels: 8   
Opto Isolated Inputs  - 8 
Analoug Inputs -4 
Contact form: 1NO 1NC
Communication protocol: Standard Modbus RTU protocol
RS485 address: 1~255
LED indicators:
STA: MCU indicator, Power ON 
TXD: TX indicator, light up when sending data
RXD: RX indicator, light up when receiving data