Friday, 31 July 2015

Turning a high powered dc motor in both directions with relays

In this post I will show you how you can turn a high powered dc motor in both direction with relays. It's very simple to do it, for this you need 2 or 4 relays.

The first option. With 2 relays: One relay to make the motor to turn in one direction, and another one relay to make it turn in the other direction. As you can see in th picture below.

Wiring 2 relays:
You connect boths nc pins to nagativeof the battery. And both no pins to positive. And both motor wires to com pins.
Now turn on and off relay1 to make the motor turn one direction. Aand turn on and off the relay2 to make the motor turn other direction. This is the safest option of the two and I prefer this one the most.

The second option. with 4 relays: Two relays to make the motor to turn in one direction. And another two relays to make it turn in the other direction. As you can see in the picture below.

Wiring 4 relays:
Well, this one is bit complicated. First you need to divide 4 relays into two and two. Then join both COM pins of relay1 and relay4 and connect it to nagative of the battery. Then join both COM pins of relay2 and relay3 and connect it to positive of the battery. Now join NO pin of relay1 and NO pin of relay3 and connect it to motor. That's one moto wire). And join NC pin of relay2 and NC pin of relay4 and connect it to the motor. That's another wire of the motor, as shown in the picture below.

 Caution: Never give connection to all the relays at once. Or never connect to a system which gives connection to all the relays at once. Because when you give connection to all the relays at once. It connects the negative and positive of the battery at the same time. And that may cause fire if the battery is powerful enough . See the picture below.

Note: This note is specially for Arduino users. Please keep in mind that if you connect the relays with Arduino by using normal method. Then it will cause a problem, because Arduino gives connection to all the relays at once when it starts.

What is a COM pin? Com pin a middle pin of a relay which connects other pins.

Thursday, 30 July 2015

Serial port com2-com3-com4-com5 not found Arduino

Right, so you might having the exact same problem that I had, but don't worry I've solved mine so you can solve yours too.
You just need to keep few things in your mind and think why is this happening? And please don't do foolish thing like I did which was completely unnecessary and waste of time. I've uninstalled my Arduino IDE because I thought something gone wrong with the IDE, then I "system restored" my computer which was even worse, because I had to reinstall so many software again and I lost too much time in that too. Any way coming to the main point, so what you going do? when you see

Serial port com2 not found or
Serial port com3 not found or
Serial port com4 not found or
Serial port com5 not found

Well, first thing you should do is go on the "Tools" in your Arduino IDE then go down in the drop down menu you will see "Serial Port" if you see it in gray color (like the picture at top) that means something wrong with your USB2.0-Serial driver or driver for your specific Arduino board *you can see my other post for that I've written in detail how to tackle with that problem* but if have already installed that and you are sure nothing wrong with the driver then unplug you arduino borad and plug it again then open your computer's "Device Manager" over here you suppose to "Ports (COM & LTP) like the picture shown below.

Step 2. If you don't find "Ports (COM & LTP) then look at your Arduino bord. If you the light of your Arduino board is dim that means it's time for you to buy another board I mean the board is damaged and that's why it is not working.

Summary: If you see serial port com2 or com3or com4 or com5 not found then that means two things
 a) You have a problem with your USB Serial driver or you need a driver for your borad.
 b) Your Arduino board is damaged and that's why it will no longer work.

Have you found the solution? Please let me know in the comment below. Thanks

Monday, 27 July 2015

Inside of a SRD-05VDC-SL-C relay and how to wire it up?

In this post you'll be able to see how does a SRD-05VDC-SL-C relay looks like from inside and how to wire it up?

  • Ok, first let me show you the pins and views from up and down and from different angle.
view from top and bottom

Front view and pins NO,COM and NC

You might be thinking why did I break the plastic case? 
Well, actually I was working on a project "open and close an electricdoor". For that project I was needed something that can turn the motor both ways. So I though let me use 4 relays 2 for turning one direction and another 2 for other direction. But after setting everything up. I noticed something is not right. And that is when ever Arduino starts, it gives connection to every single relay. So all the relays was giving connection to the motor (negative and positive) at once which and I never wanted that.

Any way, so I though it would be better if I give connection to the main coil directly (you might need to use other method if connect it directly, otherwise you might burn your arduino board). That's why I broke the plastic case to find out which pin is for the coil.

How to wire SRD-05VDC-SL-C with Arduino?
It is very simple. Just connect the GND pin of relay to GND pin of Arduino. And VCC pin to VCC pin and for the IN pin connect to the pin that you choose in the  sketch. For example pin3 in the sketch below.

int relay = 3;

// the setup routine runs once when you press reset:
void setup() {               
  // initialize the digital pin as an output.
  pinMode(relay, OUTPUT);  

// the loop routine runs over and over again forever:
void loop() {
  digitalWrite(relay, HIGH); 
  digitalWrite(relay, LOW);  


Note: Please keep in mind for some reason "HIGH" in relay means "off" I don't know why, but you can still change high to low and low to high if you need to.

Where are the coil pins of SRD-05VDC-SL-C?
In the second picture at the top of this page. You can see two red circles, those are the pins of coil. The right hand side pin is connected direct to the GND pin.

That's all for this post and watch the video to see the relay in action. Thanks a lot :)

Wednesday, 22 July 2015

How to activate EE data sim without registration

Did you just buy a EE data sim and struggling how you can activate it without registering?

Well, you have come to the right place then. In this post I'm going to show few easy and simple steps to activate your data sim. (This is for UK only)

1. Insert the sim and then got this site

2. After visiting the site you'll get two options, 
a. Click below to complete your registration.
b. Click below to get online.
Choose the option b and click on the "Activate" button.

3. That's it you are done. Now you can enjoy your internet. :)


Saturday, 11 July 2015

Are aliens watching our tv shows?

As you might already have heard many scientists saying that aliens from many light years away from earth listening and watching our tv shows, but after bit of research I found it very hard to believe that, they might be able to hear us but to see? It's almost impossible for them to see us, doesn't matter how intelligent they are.

I don't want to go too much into how tv works and all that, but here are some reasons why it is impossible for them to see us unless they get the video/ image encoder from human some how.

1. The TV signals should reach them.
Our TV signals go weaker and weaker as they travel far away from earth into the space so they (aliens) need to have powerful receiver to pick the signals up, if they don't have the receiver which can pick up our extremely weak signals then how are they going to know that we are even exist? let alone about watching us.

2. Right direction.
Ok, let's say they have the powerful receiver and they can pick up our signals but they put the receiver in wrong direction. So how they going to pick it up signals if they try to pick it up from wrong direction? Will the signal go around and hit the antenna?

3. Need to have right encoder.
Ok, now let's say they have the powerful receiver and they pointing at right direction but what about signal itself? There are 2 types of  TV signals analogue and digital each signal carries sounds and images, they might be able extract sound from the analogue signal but what about the image? it's not possible to create an image without the right encoder, and as for the digital signal, it is not possible at all to extract sounds or images because every single character we transmit will work as a password for the aliens.
You probably think why is that? well that's because when we use digital signals we send 1s and 0s but how the hell aliens will know this is 1 and this 0 plus they'll have some alien letters not like ours, so first of all the alien encoder won't be able to translate our letters and then it'll have difficulties to create images out of it.

OK, let's forget about aliens for a moment and think about our own planet. Imagine you have got  a TV which works on analogue signal and suddenly the local TV station stopped broadcasting the analogue signals and started broadcasting digital signals, will your TV work? No, never until you get the right encoder which receives digital signals and makes analogue signals so that your TV understands. 

Think about this, if this happens and we are still on earth, then what will happen light years away where alien can't figure it out what we are doing with it.

So I'm 99.999999999% sure that they won't be able to watch our TV shows likewise we can't see theirs, and if some one still thinks they (aliens) can watch our TV shows then I don't have anything to say to those people who don't used their brains! 

What about you? Do you think they can watch?