Peltier cooler

Hey guys, I am new to the programming field and also to the arduino field. I am willing to go for a project wherein I will be using the peltiers as cooling system. I did a lot of research and just found a video here: https://youtu.be/Lxbqrydr_Ck . I would like to proceed with this project with no connection problems ( because I am good at electronics). But the main thing I am lagging behind is the code. I asked the person but he has unfortunately lost the code and the project file saved on his pc. So can anyone please help me by getting the code for this project?
Requirements of the project:

  1. A touchscreen display which should should show the current temperature.

  2. A user interface that allows the user to set the desired temperature(as shown in the video).

  3. A peltier controlling system that should switch off automatically after the cooling temperature is reached to the setpoint.

  4. A progress bar showing the progress status.(as shown in the video).

Just take it one step at a time...

The LCD & touchscreen are probably the most difficult parts.

I'd break-up the project into the following parts:

  • Write information to the LCD.

  • Read the touch screen.

  • Read the temperature.

  • Turn the Peltier device on & off under software control.

I usually like to start with the easy part, so I'd probably start with the temperature sensor. Then add the Peltier on/off control, and then I'd hard-program the Peltier to hold some preset temperature with no user interface and no display.

If you want to simplify it a bit more, you can start with an LED (possibly the Pin-13 LED already on the board) in place of the Peltier and then heat & cool the temperature with a hair dryer & ice to see if the LED goes on/off when the Peltier should be going on/off.

But the main thing I am lagging behind is the code.

Read-through the language reference to get familiar with what the Arduino can do (the LCD will require an additional library, but don't worry about that yet). You won't understand or remember everything, but it won't take long to read-through the entire language reference.

Then, look through some of the examples and try some of the examples. Try to understand what the code is doing.

The two most important concepts in programming are conditional execution (if-statements, etc.) and looping (doing things over-and-over, usually until some condition is reached.

Once you understand if-statements and loops, you should be able to begin structuring your program.

When you write your program, write, compile and test (and debug if necessary) one or two lines of code at a time. The biggest mistake beginning programmers make is to write the whole program at once.... Then, the complier reports hundreds of meaningless error messages and you're stuck...

This isn't as easy as starting at the top of your program and working down... i.e. If you delete the bottom half of a program, it won't compile... You have to "develop" your code in a way that makes sense to the compiler.

As you develop your code, make use of the serial monitor so you can "see" what your program is doing. You can send messages such as "Turning-on Peltier", or you can send variable values or raw ADC readings from your temperature sensor and the resulting temperature calculations, etc.

Once your LCD screen is working reliably, you can also send test/debug information to the LCD instead of to your computer screen via the serial monitor. You might even be able to create a "debug" mode that you enter via your touchscreen!

Please supply more information on the actual project.

Peltier devices are not the most efficient devices.

Your program will also require hysteresis to be included.

Weedpharma

What are you trying to cool, or are you simply building a beer can cooler. Peltier coolers are very inefficient so you must allow for a high power consumption.

"Once you understand if-statements and loops, you should be able to begin structuring your program."

Well, I have learnt the C programming. I Know about the if statements,if-else statements and while loops too. But the thing is, I am not getting an idea on how to arrange the commands and in which series I need to arrange them. Also I am confused about the examples for giving the inputs.

mauried: What are you trying to cool, or are you simply building a beer can cooler. Peltier coolers are very inefficient so you must allow for a high power consumption.

Well, I know that peltiers are not that efficient but still as a project I would like to take this up. And I am not trying to cool a beer can but instead I would make a chamber wherein it will cool whatever is kept inside it. A mini cooler like.

pavankumarp: Well, I know that peltiers are not that efficient but still as a project I would like to take this up. And I am not trying to cool a beer can but instead I would make a chamber wherein it will cool whatever is kept inside it. A mini cooler like.

Actually the Peltier device's efficiency is keyed to the removal of heat from the device. Most users have an air cooled heat sink with a fan to move the heated air. If you watch the video, you see the maker uses water cooling to remove the heat. Very efficient and that is why the cooling chamber has frost on it.

I would ask the OP if he has the machining capability to put the cooling chamber, an aluminum block, in a lathe with a 4-jaw chuck and bore a hole to fit a soda can? Can you machine the water cooling plates to attach to the 4 Peltier devices? can you build the water cooling system, pump and radiator to do the cooling?

Paul

pavankumarp: But the thing is, I am not getting an idea on how to arrange the commands and in which series I need to arrange them. Also I am confused about the examples for giving the inputs.

That's a great indication that you should start with something simpler and work your way up.

Efficient? No. That's just applying more horsepower to the problem. I calculate that it's using at least 600W, possibly as much as 1000W. That's a pretty good room heater. Your average domestic refrigerator doesn't noticeably heat up the room does it?

You may notice that the original video only tries to cool one can. Putting the second one in with frost in the chamber could be a little difficult.

Peltiers are best used when you need a small spot of cooling, like cooling a single chip on an electronics board or less than 6 cans of drink. It's also a fun idea, which is what the original video demonstrated.

If you are trying to cool some kind of chamber or small box , then the first task you should do is calculate the thermal characteristics of the box. ie how big is it , what will it be insulated with, whats the thermal loss . Peltiers are extremely poor at this , and you need to know how many peltier modules are needed before looking at the control electronics.