> **Source:** Core Electronics is an Australian maker-electronics retailer and manufacturer based in Newcastle, NSW, run by a team of makers and educators. We design and manufacture our own product lines (PiicoDev, CE originals) and are official retailers for iconic maker and industrial brands including Raspberry Pi, Arduino, Adafruit, SparkFun and DFRobot. Orders ship Australia-wide from our Newcastle warehouse. Prices are in AUD and include GST. Pricing, stock and dispatch on this page are generated from the store's live catalog. Full machine-readable index: https://core-electronics.com.au/llms.txt

# Gravity: 4 Channel Relay Shield for Arduino

**Type:** Product page · **SKU:** DFR0144 · **Brand:** [DFRobot](https://core-electronics.com.au/brands/dfrobot-australia)
**Page:** https://core-electronics.com.au/relay-shield-for-arduino-v2-1.html ([markdown](https://core-electronics.com.au/relay-shield-for-arduino-v2-1.html.md))

This DFRoobot relay shield V2.1 is a completely new desgin which is capable of controlling 4 relays. The max switching power could be DC 90W or AC 360VA.

> ⚠ Updated on 15-OCT-20, was previously called a Relay Shield for Arduino V2.1

## Pricing

- **Price:** $26.70 (inc GST) — $24.27 AUD, exc GST
- **Quantity discounts:** 6+ $23.05 (exc GST) · 12+ $22.09 (exc GST)

## Availability & dispatch

- In stock, ships same business day if ordered before 2PM (Australia/Sydney).
- We can dispatch 1 today, and up to 300 more in 8–12 days.

## How to buy

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## Description

This Relay Shield for Arduino acts like a switch. It is commonly used to control anything over 5V such as lamps, water pumps and garage doors.

One of the most interesting projects for your boards is perhaps being able to control High power devices like Lamps, water pumps, garage doors and so on. But interfacing with high power and AC is quite a dangerous task when building the circuitry. Relays allow for interfacing an external electrical circuit like a switch. With relays you can now connect external circuit or devices directly to your Arduino.

This Arduino Shield is a completely newly designed that is able to control 4 relays at a time. The max switching power DC 90W or AC 360VA gives direct control by Arduino Uno/DFRduino controllers through digital I/Os with external 9V supply. With built-in Xbee socket, it can be wireless remote controlled via Xbee/bluetooth/WPM.

This arduino relay shield is an ideal solution for home automation and robotics applications.

*NOTE:The Arduino board requires an external power supply to drive the xbee module and relays.*

**Warning: Pay special attention to the voltage that is over 38 volts.**

**Features**

- Compatible with Arduino UNO Rev3
- Each Relay has its own test button to test the connection
- Standard DFRobot 3 Pin out
- XBee I/O direct control
 
**Specifications**

- Compatible with Arduino Rev3
- 4 buttons to test module
- LED status indicator of relay
- Support Xbee IO directly control
- Xbee socket for wireless communication
- Selectable digital IO pin for control(Default digital 2,7,8,10)
- 6 channels Analog IO & 13 channels Digital IO
- Up to 4 Relay with photo-coupled circuit
- Contact Rating 3A AC 120V / DC 24V
- Max Switching Voltage AC 240V / DC 60V (Less than 38V is recommended)
- Max Switching Current 5A
- Max Switching Power AC 360VA / DC 90W
- Electrical Life (Min) 100,000 Operations
- Mechanical Life (Min) 10,000,000 Operations
- Safety Standard(relay) UL cUL TUV CQC
- Coil Working Voltage 9VDC
- Working temperature -30℃ to +85℃
- Working Humidity 40% - 85%
- Size:95x65mm
 
**Documents**

- [Wiki (Relay Shield for Arduino V2.1)](https://www.dfrobot.com/wiki/index.php/Relay_Shield_for_Arduino_V2.1_(SKU:DFR0144))
- [Schematics](https://image.dfrobot.com/image/data/DFR0144/V2.1/Relay%20shield%20Schematic%20V2.1.pdf)
- [Board Layout](https://image.dfrobot.com/image/data/DFR0144/V2.1/Relay%20Shield%20V2.1%20Layout.pdf)
- [Sample code](https://image.dfrobot.com/image/data/DFR0144/V2.1/Relay%20shield%20V2.1%20Sample%20code.zip)
- [HJR4102 datasheet](https://image.dfrobot.com/image/data/DFR0144/V2.1/HJR-4102-L-05V.pdf)
 
**Shipping List**

- Relay Shield for Arduino V2.1 x1
- Nylon stand-off with screw x2

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/d/f/dfr0144-1.jpg)