Remote control via GPRS/GSM SMS.

Remote control, it has been a very profound things in the past. When I was a child, I always imagine that I have an equipment which can control all home appliances. Now, this has become a reality, and it is quite easy. Then I will step by step to show you how to remote control your home appliances via the GPRS/GSM SMS and relays.

At first, let me give a brief introduction about relay to you.
Relays are used where it is necessary to control a circuit by a low-power signal (with complete electrical isolation between control and controlled circuits), or where several circuits must be controlled by one signal. It acts as a “low voltage controlled switch to control high voltage”, For example, if you want to control power of your washer or air conditioner, which is oftern110v or 220v,by microchip, such as AVR or PIC, it is necessary and safe the make your microchip control the relay first, and then control the power supply of those device with the relay.

With the GSM SMS, it is possible to control the relay remotely. You can send a message via phone to control the relay on&off. With this, it will convenient to control any device wirelessly, especially helpfully on irrigation, smart home, outdoor remote control etc.
So, let’s make such a “SMS control relay” with Arduino, GPRS/GSM and a Relay module.

Step 1: Prepare your tools and parts.

Select the module you need, a Xrduino, a GPRS/GSM module and relay module is essential. The GPRS/GSM and relay in “Shield” would be more Convenient if works with Arduino. Notice that the Rated Current of the relay Is important, make sure it meets your requirements. Otherwise it maybe dangerous. Here, I use a 2A rating current relay, which is enough for my application to control a lamp. Usually, home appliances consume currents as below:
Device                          Max current(A)
Electric Fan                            1
Lamp                                       2
TV                                             2
Refrigerator                            2
Microwave Oven                    8
Air Conditioner Depends on the power, usually <20

The modules I used in this application are as below:
Crowduino
Elecrow GPRS/GSM Shield
Elecrow Relay Shield

Comments

[nightcrawler218]

Hello,

This tutorial is very very useful. I am trying to demonstrate this project on my own. I am using SIM300 gsm module because I don't have a gsm shield for arduino. However, the relay control part is working fine BUT the problem is that SIM300 has only 25 sms memory. I want to delete the sms memory after every "reset" or after executing ona, onb, onc, ond etc.

So, I added the code in Void Setup()
but it is not working.
Serial.write("AT+CMGDA=");
Serial.write(34); //ASCII of “
Serial.write("DEL ALL");
Serial.write(34);
Serial.write(13);
Serial.write(10);
delay(10000);

I have written the details & result of my experiment in this post.

http://arduino.cc/forum/index.php/topic,155448.msg1165394.html#msg1165394

Any help shall be highly appreciated.
Thanks

[Elecrow]

Nice job!