Relay Shield

Introduction

The Relay Shield is an Arduino compatible smart module with 4 mechanical relays providing an easy way to control high voltage. The max switching power is 35VDC 70W for each channel. It can be directly controlled by Arduino through digital IOs with external 9V DC supply. With the XBee form socket and 315/433MHz RF module interface, the Relay shield can be remotely controlled, making it easy to use in robotics, industry control, smart houses etc.
Note: Take care the pins on the Shield should not be touched with USB connector of Arduino UNO when they are connected .

Features

• Arduino, Arduino Mega compatible
• 4 mechanical relays with photo-coupled circuit
• Equipped with screw holes for easy installation
• Light weight
• Small form factor
• Native Arduino compatibility
• Extendible

Specification

Item	Min	Typical	Max	Unit
Voltage	7	9	12	VDC
Current	8	/	250	mA
Switching Voltage	/	/	35	VDC
Switching Current	/	/	2	A
Frequency Response	-1	/	1	dB
Switching Power	/	/	70	W
Relay Life	100,000	/	/	Cycle
ESD contact discharge	±4			KV
ESD air discharge	±8			/
Dimension	80.0x58.0x21.2			mm
Net Weight	31±2			g

Interface Function

4 groups of channels for High voltage connection
Terminal 1:
COM1- Common pin
NC1- Normally Closed, in which case NC1 is connected with COM1 when D0 is set low and disconnected when D0 is high;
NO1- Normally Open, in which case NO1 is disconnected with COM1 when D0 is set low and connected when D0 is high.
Terminal 2-4 are similar to terminal 1, except that the control ports are D1-D3.

9V DC power supply connection
The function of the Terminal and the Jack is the same since they are internally connected, and you can choose either of them in needs.

IO controlling 4 on-board relays
D0-D3 4pins could be connected directly with Arduino pin number of 7-4, so that four relays could be easily controlled by the Arduino.

315/433MHz RF control interface
Together with pin of GND and 5V, they are the interface for 315/433MHz RF with encoder module (can be bought separately from Seeed Studio) to control the 4 relays remotely.

XBee form Socket for directly control by Xbee
The 4 relays can be directly controlled by the Xbee through the 4 DIO ports of Xbee

RFBee cascading control interface
As the RFBee has 12 DIO ports, 2 more Relay Shield (8 more relays) could be controlled through one RFBee. HUB1 and HUB2 are the drawn-out ports of RFBee (4 as a group), which is connected to 315/433MHz RF interface of the cascading Relay Shield.