Hi,
I have emontx, nanoderf base and emoncms setup for testing.
All works well, but the measurements are wayyyy off for CT2 and CT3 inputs ! (with or without CTs attached).
In no load condition, the values are:
0-3 watts , 25-40 watts, 40-45 watts for CT1, CT2 and CT3 respectively.
I have read elsewhere that there could be noice issues, but can someone confirm their noise levels on CT1? I believe there maybe some other small issue in software coz the error % gap with each input seems constant, and the error rate is also very consistent (irrespective of interchanging CTS or removing them, or moving to another room for testing.. nothing helps).
Once the load is there (60 watts bulb), then the situation reverses !!
70-72 watts,66-68 watts, 63-65 watts for CT1,CT2 and CT3 respectively
CT1 has highest error 70-72 watts, I may be paranoid, but I think if others are experiencing the same pattern as above, then we can probably drill deeper.
Cheers!
Re: EmonTX currrent only > consistant error in measurement
You might like to look at these:
http://openenergymonitor.org/emon/buildingblocks/measurement-implication...
http://openenergymonitor.org/emon/emontx/accuracy
http://openenergymonitor.org/emon/node/1385
http://openenergymonitor.org/emon/node/2311
Trystan did some wonderful animated pages demonstrating how the errors vary here: http://vis.openenergymonitor.org/dev/adc/noiseless, here: http://vis.openenergymonitor.org/dev/adc/noisy and here: http://vis.openenergymonitor.org/dev/adc/noise.mp4.