Arduino Fun...Detection

Well I have tried some of the detection devices available off ebay, and I couldn't get any of them to see the load and report stable usable data....until tonight. Thanks Trevor for your assistance.

Today I found a few web links using the ACS712 Hall Effect Current Sensor Module, I have one and had tried this first but it wasn't stable enough to use and didn't detect the small current draw by sound loco's ;et alone non sound loco's

I found this YouTube clip that the chap had added 470PF cap to it to make it stable, Trevor supplied the cap and some time and we had a look at it, but still couldn't make it stable. I had a few other types that I had previously tried but without much success but it had only been a half hearted attempt to make them work. As reliable detection is coming to the top of the list for all my fellow enthusiast at the moment I decided to give it another go in earnest.

With Trevor's help we managed to get one unit working very reliably on all loco's, good news considering it costs $5 aprox and is a toroidal type so polarity is not an issue. The issue is though we had to squeeze 7 wraps of the conductor through it, i ended up going down to .7mmsq retic wire and it was tight, another 3 wraps was the target. Will need to obtain some suitable magnet wire (varnished copper) and give it a try. None the less the 7 wraps worked very reliably, but it is at the very lowest point in the scale, and one in about 30 samples results in a 0 which would report a loss of detection in that block to Loconet... we could mask this out in logic, but these things are going to have to be in minimal numbers on an Arduino as it hogs the processor through sampling rate. Not such a big issue, just drop the rate from .25 of a second to 1 second...that's quick enough for what we need. True but if the sample happens to be the zero then no detection.

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IMG_1935 (Copy)

It is the most promising we have had yet fro cheap detection and I need to do some more work, see how the Arduino will go running the max(7 on a nano) and still monitor the 7 digitals a swell as report to Loconet the status change. Don't think it will be too much of an issue but un tested as yet.....

So off to ebay to buy some magnet wire......now what size?? thinking 19AWG close to 1mmsq copper, only issue is got to buy so much and it takes 4 weeks from china...might have to try Jcar this week.

will keep you posted.