Simple ammeter/amp-hour meter
 

I've just made an ammeter/amp-hour meter if anyone's interested. It uses a Tamura current sensor, a 16 x 2 LCD and a small pcb with a PIC micro on board.
The display shows Amps flowing through whatever cable you stick the sensor on and Amp-Hours accumulated since the last rest. The range is 0 - 511 amps and it measures about 82 x 41 mm. It needs 12 V power and is completely isolated from whatever you are measuring.
Parts cost is around $40 if you want to build your own or I can sell you a completed one - without case - for $99.
Send a PM if interested.

Although I'm not interested in buying one, I'm interested in the design details. I'm sure there are others as well. Can you post it?

Thx

I'll give it a shot- here' a picture and some pcb layouts. The schematic was too big to upload, I'll see if I can squeeze it down a bit.

SS = silk screen, TC = top copper, BC = bottom

Attachment 12367

Attachment 12368

Attachment 12369

Attachment 12370

Here's the schematic as a zipped .pdf.

Attachment 12379

Here's the C source code. Compiled with the CCS C compiler running on MPLAB IDE V 8.88. The micro is a PIC16F1826, current sensor is Tamura L01Z400S05.

Attachment 12380

Should be enough info to make one!
The sch and pcb files are DesignSpark

Nice, thank you.

I finally got around to putting all the files together in one place, so here they are:
Attachment 12382

The .sch and .pcb files are DesignSpark. The source code files are compiled with CCS C compiler running under MPLAB V 8.88 and the .mcp file is the project file for this.

You can make a 255 A version by changing to a Tamura 200 A sensor with some other minor changes.

Hi, Is it possible to get the .hex file from you to program into the chip. I treid Mplab but it gives an error message when I try to build the project.
I want to adapt the circuit to read current trough a load and give me A/Hour reading. This is to test battery capacity.

The .ASM file will also work.

Are you using the CCS compiler in MPLAB.
You need to use the same compiler as the source code was written for otherwise MPLAB will throw errors.
The other option is to alter the source code to be compatible with whatever compiler you are using.

Thanks it seem to work now. I will build it and try it.