Part 10 – HHO Project – Intro To Arduino

This is a continuation of the first post – Is It Possible To Build A Computer Controlled Feedback Circuit For HHO Generator? My personal discovery of the invention developed by Stanley Meyers, a Voltage Intensifying Circuit with very low amperage.

Well, I have made the big commitment, and I am lovin’ it so far!

I ordered off for my Arduino from SparkFun, and it came well packed and fully assembled. Plug it into a USB printer cable, and after a detailed install, that worked the first time, my first test program started perfectly.

I have begun to get a handle on how it will interface with all of what I have all ready built. My original direction was to use a Velleman USB Interface card and use desktop computer to make all of the calculations and send it back though to the relays, sensors and coils. So I bought and put together the Velleman Relay Card K2633. You can look back at that build in Part 8.

The job of the Relay card is to turn on a pump to fill the fuel cell as need from a supply tank, and a safety control connection to the main power to the cell.

Now I did some Googling, and could not come up with a clear connection to an Arduino. I found each side, so I combined them.

Protecting the Arduino is very important,

and making 5 volts talk to 9 volts is easy if you know the trick. It comes in a neat little 6 pin dip package with a long name. Opto-Isolation, a reliable barrier that can also handle the translation of signal problem. It is also simple in the construction which can not be seen. Inside is an LED that shines on a NPN Photo Transistor, with no physical electrical connection.

I picked a NTE3045, not because I truly understand the requirements of the load from the relay card, and there may be a better one for the job, but as I have hooked it up, and looked at the easy wiring, loads and robustness, and I like it. To make an LED work on the Arduino side you just put a resistor in the siginal path to control the load and that it. I am using a 680 ohm resistors, and it is giving the nominal 1.8 volts to the Opto-Isolator input.

Now for the all important hook up on the relay side, don’t be disappointed in the simple. I just grounded the Darlington on the 9 volt ground and sent the other side to the input pins of the card. Boring wasn’t it? The card, like it should, is taking care of all of the rest of the circuit. It is wonderful. So after getting confident in the bread board I built a permanent one to handle all four signals, and make it clean, easy to test,and terminal screw downs for the wires over to the other boards. The photo only show one Opto and one signal wire, the other three are not here yet.

Connecting a relay to the Arduino could have been done many other ways, but I all ready had the Velleman card, and I got the strong bonus of the isolation, that I will need to dive deeper into as I go.

Understanding the software has been a joy of simplicity. It has been so easy to make real programming happen with the great examples built right in the program of the compiler language. Built around C the structure is familiar and logical to follow. YouTube leasons are plentiful with a fully stocked website of current projects. I all ready have the LCD readout, the float switch and a temperature sensor working. More details later.

Make Magazine loves it the Arduino, and you should see what every one else is doing with this little micro controller. WOW! and Open Source! You can even sew one into your cloths.

It is like I am building a house, one nail, one board at a time, but I see the vision on where I am going, and it is looking good.

Posted by: Ron G.