8-Channel ESP32-S3 WiFi Relay Module with RS485 (PoE Option)

This is an 8-channel WiFi relay module from Waveshare, controlled by an ESP32-S3, with isolated RS485 interface and optional 802.3af PoE support, along with a range of features that make this an ideal relay solution for advanced home automation projects or commercial settings.

It combines Wi-Fi, Bluetooth LE, Ethernet and RS485 connectivity with eight high-quality relays and eight digital inputs. Each relay is rated up to 10A at 250VAC or 30VDC, allowing direct control of mains-powered equipment or low-voltage devices. The board supports both passive (dry contact) and active (wet contact) digital inputs, with bi-directional optocoupler isolation to ensure stable operation and protect against electrical interference.

An isolated RS485 interface enables connection to Modbus devices and industrial sensors, with onboard termination support for reliable communication.

Wired network connectivity is handled by the W5500 Ethernet controller for 10/100Mbps wired networking, with optional IEEE 802.3af PoE functionality, allowing power and data to be delivered over Ethernet. Power can also be supplied via USB-C or a wide-range 7–36V DC screw terminal.

The module includes protection features, including power isolation, digital isolation, optocoupler isolation and TVS surge suppression, helping safeguard both the relays and connected equipment. An onboard RTC supports scheduled tasks, while a MicroSD card slot allows local storage of files or data. Status LEDs, a buzzer and an RGB LED provide clear visual and audible feedback, and the unit is housed in a rail-mountable ABS enclosure for easy installation in control cabinets.

We offer a version of this product with a PoE module, please select an option before adding to cart.

What's Onboard?

1. ESP32-S3-WROOM-1U-N16R8
   • Uses the ESP32-S3 series chip with a Xtensa 32-bit LX7 dual-core processor
   • Built-in 16MB Flash and 8MB PSRAM
2. 2-channel relay
   • Contact rating per channel: ≤ 10A at 250V AC or ≤ 10A at 30V DC
3. Optocoupler isolation
   • Prevents interference from external high-voltage circuits connected to the relay
4. RESET button
5. PoE header
   • Supports connection to a PoE module for Power over Ethernet capability (PoE port version only, via module)
6. BOOT button
7. Power IC
8. Digital isolation
   • Prevents interference from external signals
9. Power supply isolation
   • Provides a stable isolated voltage
   • No additional power supply required for the isolated terminal
10. Bi-directional optocoupler isolation
11. RTC battery holder
    • Supports rechargeable CR1220 size batteries (12mm diameter, 2mm thickness)
    • Compatible with rechargeable 3V–3.3V batteries only
12. Buzzer
13. Digital input screw terminals
14. Pin header
    • For connecting additional devices
15. LED indicators
    • PWR: power indicator
    • RXD: RS485 receive indicator
    • TXD: RS485 transmit indicator
16. USB-C connector
    • For module power supply
    • Supports firmware flashing and USB communication
17. WS2812 RGB LED
    • Controlled via GPIO38
18. Ethernet port
19. External antenna connector
    • SMA female connector for Wi-Fi and Bluetooth wireless communication
20. Power supply screw terminal
    • Supports wide voltage input from DC 7V to 36V
21. RS485 communication interface
    • For connecting external RS485 devices
22. RS485 matching resistor jumper
    • Onboard reserved 120Ω termination resistor
    • Enabled via jumper
23. Relay screw terminals

24. Onboard TVS (Transient Voltage Suppressor)
    • Effectively suppresses surge voltage and transient voltage spikes in the circuit
25. RS485 conversion chip
26. MP1605GTF-Z
    • DC-DC power module
27. PCF85063ATL
    • RTC chip capable of supporting scheduled tasks
28. TCA9554PWR
    • GPIO expansion chip
29. W5500
    • Provides a 10/100Mbps network port via SPI interface
30. MicroSD card slot
    • Supports external MicroSD card storage for images and files

Features

• ESP32-S3 microcontroller with Xtensa 32-bit LX7 dual-core processor, up to 240MHz
• Integrated 2.4GHz Wi-Fi and Bluetooth LE dual-mode wireless connectivity
• 8 High-quality relays rated at ≤10A, 250V AC or 30V DC (1NO 1NC)
• Supports passive and active digital inputs with bi-directional optocoupler isolation
• Relay supports digital input linkage control
• Isolated RS485 interface for connection to RS485 Modbus industrial modules and sensors
• Pin header for connecting additional devices
• USB-C port for power, firmware flashing, and debugging
• Power supply screw terminal supporting a wide 7–36V DC input range
• Onboard RTC supporting scheduled tasks
• W5500 Ethernet controller providing a 10/100Mbps network port via SPI
• Optocoupler isolation to protect against interference from external high-voltage relay circuits
• Digital isolation to prevent interference from external signals
• Integrated power supply isolation
• MicroSD card slot
• Built-in buzzer, RGB LED, and power and RS485 TX/RX status indicators
• DIN rail-mountable ABS enclosure
• Optional: PoE support via built-in PoE module compliant with IEEE 802.3af

Resources

• Product documentation

Package Contents

• 1x 8-Channel ESP32-S3 WiFi Relay Module with RS485
• 1x 2.4Ghz 4DB SMA antenna
• 1x Screwdriver
• Optional (see variant):
  • PoE support (via internal installed module)