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View Full Version : Help! How do I make a LCD to display the individual cells on my lipos?

tukkus
Feb 23, 2009, 03:12 PM
Hello,

Now that I'm getting addicted to the 450 size helis and can foresee them being a bigger part of the hobby for me, I'd like to make an LCD that will show the voltage for the individual cells in a 3S and maybe up to a 4S for my lipo packs.

I have 3 Hobbico Elite chargers and a Thunder Power 205v balancer, neither unit shows what the individual cell voltage is, I can get the packs balanced but I'd just like to see the voltages for each cell for closer monitoring.

I'm not sure if there any device that's being sold that would do that, I've looked around and haven't found anything, so I figured that maybe it wouldn't be that difficult to make it a DIY project and maybe I can learn a thing or two along the way and save a couple of bucks too.

I can't imagine that this thing would be expensive but I really have no Idea what is needed to complete my project.

I know that I'll need a few items like...

LCD
connector
board

My problem is that I have no experience in this field and need some guidance on what else is needed and how to put it together.

I'm hoping this is a simple enough project that someone can point me in the right direction on how to build this.

thanks for any advice
Ron W3FJW
Feb 23, 2009, 03:58 PM
HC has several different types. Here's one of them.
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6589
With monitors selling for between $5 to $10, it's not hardly worth the effort to DIY unles one is a diehard DIYer.
tukkus
Feb 23, 2009, 05:37 PM
thank you for the link
Almaz
Feb 23, 2009, 05:48 PM
If you wish to make something custom I can write you a program for Microchip. It'll take me about 20 minutes anyway. You would need to put it together. LCD, Microchip, 5v regulator, RadioShack board and 3-4 capacitors and a few resistors. Total cost should be around $20. You can read up to 8 cells voltage on LCD at the same time and it can show total voltage as well. You can even use a computer serial port instead of LCD to output all the values on the screen. Using Microsoft excel you can have a real time graph showing the percentage. It all depends how much fun you wish to have with the project.
gta18
Feb 28, 2009, 12:41 AM
@almaz

I'll take your program. If you don't mind. coz am trying to build one myself. specially the computer interfaced one. It takes me forever to figure out how to do that. if you can write it using c18 compiler for the 18f4550.

Thanks
Almaz
Feb 28, 2009, 02:57 AM
@almaz

I'll take your program. If you don't mind. coz am trying to build one myself. specially the computer interfaced one. It takes me forever to figure out how to do that. if you can write it using c18 compiler for the 18f4550.

Thanks


Not a problem. I'm using Proton PicBasic compiler instead of C18 compiler. Proton PicBasic is much easier than C and it only takes one line in basic compare to 10 lines in C. Check out lite free edition http://www.picbasic.org/proton_lite.php Tell me exactly what do you want from the project. I don't know how to use USB interface but a standard Serial port is easy. If you don't have a serial port in your computer then you can just buy Serial to USB converter and it'll work just the same. What experience do you have with microchip and electronics? 18F4550 is kind of overkill for such a simple job but if that's what you have, it'll work great but if you decide to use free lite edition of Proton PIcBasic then you need to use a different pic which supported under free version. Here is a similar project to what you wish to do with an example and video http://www.digital-diy.net/16F%20Examples/ADC.aspx