8-ch Ethernet Relay Module (B) With Digital Input, Modbus RTU/Modbus TCP Protocol, PoE Port Communication

The Modbus PoE ETH Relay Board by Waveshare is a versatile industrial control module designed for remote monitoring and automation applications. It combines Power over Ethernet (PoE) functionality with Modbus TCP communication, enabling seamless integration into smart systems for controlling electrical devices.

Key Features

• Power over Ethernet (PoE) :

  • Powered via Ethernet cable (IEEE 802.3af/at), eliminating the need for separate power adapters.
  • Simplifies installation and reduces wiring complexity.

• Relay Control :

  • Equipped with 4x SPDT relays , each capable of switching up to 10A at 250V AC or 30V DC .
  • Ideal for controlling high-power devices such as lights, motors, pumps, and HVAC systems.

• Modbus TCP Protocol :

  • Supports industry-standard Modbus TCP for reliable communication in industrial environments.
  • Compatible with SCADA systems, PLCs, and other Modbus-enabled devices.

• Ethernet Connectivity :

  • Built-in Ethernet interface for networked control and monitoring.
  • Supports 10/100Mbps data transfer rates.

• Compact Design :

  • Compact form factor for easy integration into control panels or IoT setups.
  • Mounting holes provided for secure installation.

• LED Indicators :

  • Status LEDs for power, Ethernet activity, and relay states for quick diagnostics.

• Wide Input Voltage Range :

  • Operates on 48V PoE or external DC input (optional).

• Isolation Protection :

  • Features electrical isolation to protect connected devices from voltage spikes and interference.

Features At A Glance

This product is an industrial 8-ch relay module controlled via Ethernet port, with 8-ch digital input, adopts Modbus RTU/Modbus TCP protocols, supports PoE power supply, also comes with an ABS rail-mount case.

The Modbus POE ETH Relay (B) is very easy to use. Due to its fast communication, stability, reliability, and safety, it is an ideal choice for industrial control equipments and/or applications with high communication requirements.

• 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
• Supports DC 7~36V wide range power input and PoE power supply
• Supports relay control through MQTT protocol, comes with Alibaba Cloud MQTT application demo
• Onboard Optocoupler isolation, prevent the relay from being interfered by high-voltage circuit
• Adopts dedicated relay driver chip, with built-in flyback diode protection, for stronger and more stable driving ability
• Supports passive and active digital input, with bi-directional optocoupler isolation, built in debouncing algorithm. The relay supports digital input linkage control or toggle control
• Reverse-proof circuit, prevent the circuit from being damaged accidentally by incorrect connection
• High quality relay, contact rating: ≤10A 250VAC/30VDC
• Rail-mounted ABS plastic enclosure, easy to install, safe to use
• 4 LEDs and Network indicators for indicating the MCU status and signal transceiving status

Primary function

Supports reading digital input by sending Modbus RTU protocol commands via Ethernet for relay output control

Supports Multiple Communication Modes, Adopts Modbus Protocol

Supports TCP Server / TCP Client / UDP Mode / UDP Multicast / HTTP / MQTT
Supports Modbus RTU protocol/Modbus TCP protocol

Multi Configuration Methods

Supports software and Web Browser Configuration, Obtaining Dynamic IP Via DHCP, connecting to domain name server via DNS protocol

Multi Power Supply Options, Wide Range Power Input

DC Power port: directly uses a power plug for power supply; Screw terminal: DC 7~36V wide range power input; PoE port: IEEE 802.3af PoE compliant

* The external power supply adapter is NOT included by default, it is recommended to purchase 12V power supply if you need it.

Digital Input

Supports passive (dry contact) and active (wet contact) digital input, with bi-directional optocoupler isolation

Interfaces & Indicators

With Multiple LED Indicators, Easy To Monitor The Operating Status

Multiple modes for various automation scenarios

Supports multiple relay control modes, each channel supports independent
control mode setting

Relay connection

Contact rating of the onboard relay up to 10A 250VAC/30VDC
Directly controlling 220VAC home appliances, or devices below 30VDC

Enclosure Design

Rail-mounted ABS plastic enclosure, easy to install, safe to use

Applications

Product show

Outline dimensions

Resources & Services

WIKI: www.waveshare.com/wiki/Modbus_POE_ETH_Relay_(B)

Shipping list

Weight: 0.292 kg

The power supply of this product is not included, it is recommended to purchase 12V power supply if you need it.

Modbus POE ETH Relay (B) x1