Industrial 8-Channel RP2350 Relay Module (Ethernet + Isolated RS485)

Eight relay channels and eight isolated digital inputs, driven by a Raspberry Pi RP2350B and addressable over Ethernet or isolated RS485.

Wiring a microcontroller into real switchgear usually means stacking a dev board, a relay board, an isolator and a network adaptor, then finding somewhere to mount the pile. This puts the lot inside one 175 x 90 x 40mm ABS enclosure that clips straight onto 35mm DIN rail.

Isolation is handled at every boundary: optocouplers between the microcontroller and the relay drivers, bi-directional optocouplers on the digital inputs so they accept both dry and wet contacts, digital isolation on the RS485 line, and unibody power isolation that generates the isolated rail on-board - no separate supply needed for the isolated side. Each relay is rated to 10A at 250V AC or 30V DC, with both normally-open and normally-closed contacts brought out to screw terminals.

Power comes from a 7~36V screw terminal, and programming is drag-and-drop over USB-C. Waveshare provide networking demos that publish over lightweight MQTT and HTTP, and the board is supported by the C/C++ SDK, MicroPython and the Arduino IDE.

Features

• Switch AC or DC loads directly - each of the eight relays handles up to 10A at 250V AC or 30V DC, with 1NO/1NC contacts on every channel
• Read field signals safely - eight digital inputs accept 5~36V from either passive dry contacts or active NPN/PNP sensors, behind bi-directional optocoupler isolation
• Relays support digital-input linkage control, so interlock behaviour keeps running locally even if the network drops
• Talk to existing plant over isolated RS485 - hardware automatic direction control, TVS diode, surge and ESD protection, and a 120R termination resistor you can enable with a jumper
• Wired networking without a second board - an onboard W5500 provides a 10/100Mbps Ethernet port over SPI, so there is no wireless link to lose inside a metal cabinet
• Choose Arm or RISC-V on the same silicon - the RP2350B runs dual Cortex-M33 or dual Hazard3 cores at up to 150MHz, with 520KB of SRAM and 16MB of onboard flash
• Keep time and run scheduled tasks unattended - onboard PCF85063ATL RTC with a 1220 rechargeable cell holder
• Log data or store assets locally through the onboard microSD (TF) card slot
• Feed it whatever the cabinet has - 7~36V wide-range input on a screw terminal, suited to industrial supply rails
• See the state of the system at a glance - programmable WS2812 RGB LED, buzzer, power indicator and RS485 TX/RX indicators
• Mount it where it belongs - ABS protective enclosure with 35mm DIN rail support
• Flash firmware by dragging a file onto a USB mass-storage drive, and break out 15 multi-function GPIO on the onboard pin header for everything else

Specifications

Resources

• Waveshare Wiki - demo code, schematic, pin definitions and datasheets

What's Included

• 1x Industrial 8-Channel RP2350 Relay Module (RP2350-ETH-8DI-8RO)
• 1x Screwdriver