Bluetooth technology is a short distance communication technology used by almost all phones including smart phones and all laptops. This technology find very wide uses including that of Home & Industrial automation. The Relay shield is capable of controlling 4 relays. The max switching power could be 12A/250VAC or 15A/24VDC. It could be directly controlled by Arduino through digital IOs.

1. 4 Channel Relay Board -Bluetooth
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4 CHANNEL RELAY
BOARD-
BLUETOOTH

2. 4 Channel Relay Board -Bluetooth
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Table of Contents
OVERVIEW..................................................................................................................................................... 3
FEATURES.................................................................................................................................................. 3
APPLICATION DIAGRAM............................................................................................................................ 4
Bluetooth Module HC 05 .............................................................................................................................. 5
SPECIFICATION.......................................................................................................................................... 5
APPLICATION............................................................................................................................................. 5
CIRCUIT DIAGRAM ........................................................................................................................................ 6
EXPERIMENTAL SETUP .................................................................................................................................. 7
RELAY SHIELD ARDUINO CODE ................................................................................................................. 8
4-RELAY SWITCH BOARD ANDROID APPLICATION..................................................................................11
RELATED PRODUCTS ................................................................................................................................... 12

3. 4 Channel Relay Board -Bluetooth
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OVERVIEW
Bluetooth technology is a short distance communication technology used by almost all phones
including smart phones and all laptops. This technology find very wide uses including that of Home &
Industrial automation.
The Relay shield is capable of controlling 4 relays. The max switching power could be
12A/250VAC or 15A/24VDC. It could be directly controlled by Arduino through digital IOs.
FEATURES
• 4-channel Relay.
• With Bluetooth wireless interface.
• Arduino compatible.
• 4 SPDT Relay channels (10A 277VAC,10A
120VAC, 5A 250VAC).
• Power supply:5VDC 1AMP
• Current consumption: 400 mA.
• LED indication for relay & power supply.
• Design based on highly proven IC ULN2803
as driver.
• High quality PCB FR4 Grade with FPT
Certified.

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APPLICATION DIAGRAM
front view

5. 4 Channel Relay Board -Bluetooth
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back view
Bluetooth Module HC 05
Serial port Bluetooth, Drop-in replacement for wired serial connections, transparent usage. You can use
it simply for a serial port replacement to establish connection between MCU and GPS, PC to your
embedded project and etc.
SPECIFICATION
• Bluetooth protocol: Bluetooth Specification v2.0+EDR
• Frequency: 2.4GHz ISM band
• Modulation: GFSK(Gaussian Frequency Shift Keying)
• Emission power: =4dBm, Class 2
• Sensitivity: =-84dBm at 0.1% BER
• Speed: Asynchronous: 2.1Mbps(Max) / 160 kbps, Synchronous: 1Mbps/1Mbps
• Security: Authentication and encryption
• Profiles: Bluetooth serial port
• Power supply: +3.3VDC 50mA
• Working temperature: -20 ~ +75 Centigrade
• Dimension: 26.9mm x 13mm x 2.2 mm
APPLICATION
• Computer and peripheral devices
• GPS receiver
• Industrial control

6. 4 Channel Relay Board -Bluetooth
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• MCU projects
CIRCUIT DIAGRAM

7. 4 Channel Relay Board -Bluetooth
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EXPERIMENTAL SETUP
Note: remove USB after uploading the code, DC 12V 1A must be plugged in.

8. 4 Channel Relay Board -Bluetooth
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RELAY SHIELD ARDUINO CODE
/*
Software serial multiple serial test
Receives from the hardware serial, sends to software serial.
Receives from software serial, sends to hardware serial.
The circuit:
* RX is digital pin 10 (connect to TX of other device)
* TX is digital pin 11 (connect to RX of other device)
Note:
Not all pins on the Mega and Mega 2560 support change interrupts,
so only the following can be used for RX:
10, 11, 12, 13, 50, 51, 52, 53, 62, 63, 64, 65, 66, 67, 68, 69
Not all pins on the Leonardo support change interrupts,
so only the following can be used for RX:
8, 9, 10, 11, 14 (MISO), 15 (SCK), 16 (MOSI).
Software serial multple serial test
Receives from the hardware serial, sends to software serial.
Receives from software serial, sends to hardware serial.
The circuit:
* RX is digital pin 2 (connect to TX of other device)
* TX is digital pin 3 (connect to RX of other device)
SENDING DATA FORMAT
1N TO ON RELAY1
1F TO OFF RELAY1
2N TO ON RELAY2
2F TO OFF RELAY2
3N TO ON RELAY3
3F TO OFF RELAY3
4N TO ON RELAY4
4F TO OFF RELAY4
This example code is in the public domain.
*/

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#include <SoftwareSerial.h>
SoftwareSerial mySerial(2, 3); // RX, TX
int rec;
void setup()
{
pinMode(4, OUTPUT);
pinMode(5, OUTPUT);
pinMode(6, OUTPUT);
pinMode(7, OUTPUT);
mySerial.begin(9600);
}
void loop() // run over and over
{
while(!mySerial.available());
rec=mySerial.read();
if(rec=='1')
{
while(!mySerial.available());
rec=mySerial.read();
if(rec=='N')
digitalWrite(4, HIGH);
else if(rec=='F')
digitalWrite(4, LOW);
}
else if(rec=='2')
{
while(!mySerial.available());
rec=mySerial.read();
if(rec=='N')
digitalWrite(5, HIGH);
else if(rec=='F')
digitalWrite(5, LOW);
}
else if(rec=='3')
{
while(!mySerial.available());
rec=mySerial.read();
if(rec=='N')
digitalWrite(6, HIGH);

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else if(rec=='F')
digitalWrite(6, LOW);
}
else if(rec=='4')
{
while(!mySerial.available());
rec=mySerial.read();
if(rec=='N')
digitalWrite(7, HIGH);
else if(rec=='F')
digitalWrite(7, LOW);
}
}

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4-RELAY SWITCH BOARD ANDROID APPLICATION

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SOFTWARE DOWNLOAD LINK
https://drive.google.com/folderview?id=0BzrGD4zr88GnSkt5aUJMZ3Y0dnM&usp=sharing#
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