1. Onboard mature and stable 8bit MCU and MAX485 level conversion chip
2. Communication protocol: support standard Modbus RTU protocol
3. Communication interface: support RS485/TTL UART interface
4. Communication baud rate: 4800/9600/19200, default 9600bps, support power-down save
5. Optocoupler input signal range: DC3.3-30V (this input cannot be used for relay control)

6. Output signal: relay switch signal, support manual, flash, flash mode, flash/flash delay base is 0.1S, the longest flash/flash time can be set to 0xFFFF*0.1S=6553.5S
7. Device address: range 1-255, default 255, support power-down save
8. Baud rate, input signal, relay status, device address can be read by software/command
9. Onboard 4 5V, 10A/250V AC 10A/30V DC relays, which can be activated 100,000 times continuously, with diode overflow protection and short response time
10. On-board relay switch indicator light
11. Power supply voltage: DC7-24V, support DC socket/5.08mm terminal power supply, with input anti-reverse connection protection
Type: Relay Module Switch
Rated voltage: 4 Channels
color:Blue
Material:PCB

Package Contents:
1 x Relay Module