---
title: "Ethernet Shield W5100 & Control External Devices with Relay"
url: "https://maker.wiznet.io/irina/projects/Ethernet-Shield-W5100-amp-Control-External-Devices-with-Relay/"
markdown_url: "https://maker.wiznet.io/irina/projects/Ethernet-Shield-W5100-amp-Control-External-Devices-with-Relay/md"
type: "UCC: User Created Content"
author: "irina"
author_url: "https://maker.wiznet.io/irina/"
original_author: "irina"
original_url: "https://www.14core.com/wiring-ethernet-shield-w5100-control-external-devices-with-relay/"
published: "2021-06-09"
language: "en"
hardware: ["Arduino UNO R3", "ethernet shield W5100", "Resistor 220 k Ohms", "LED ( Any color ) as Oupu", "Solder Less Bread Board", "Jumper Wires", "2, or 4 channel Relay 5v Module with Isolator/Optocoupler"]
likes: 0
views: 212
comments: 0
source: "WIZnet Makers (https://maker.wiznet.io/)"
---

# Ethernet Shield W5100 & Control External Devices with Relay

> Ethernet Shield W5100 & Control External Devices with Relay

Original author: irina (source: https://www.14core.com/wiring-ethernet-shield-w5100-control-external-devices-with-relay/)

## Components

- **Arduino UNO R3** x 1
- **ethernet shield W5100** x 1
- **Resistor 220 k Ohms** x 1
- **LED ( Any color ) as Oupu** x 1
- **Solder Less Bread Board** x 1
- **Jumper Wires** x 1
- **2, or 4 channel Relay 5v Module with Isolator/Optocoupler** x 1: Optional Components

## Documents and links

- [Arduino code](https://www.14core.com/wiring-ethernet-shield-w5100-control-external-devices-with-relay/) (code)

## Article

![](https://maker.wiznet.io/uploads/2021/06/ethernet4-300x274.png) This Ethernet shiled library does not come with DNS support out of the box meaning we cannot used to access the website we need by its simple URL (like?[http://www.14core.com](https://www.14core.com/)). We need to have access the site though an IP address. For instance 192.168.10.100, 200,188,122,145 and you can actually access.

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Source: https://maker.wiznet.io/irina/projects/Ethernet-Shield-W5100-amp-Control-External-Devices-with-Relay/