emontx shows funny reading


After soldering emontx for CT1 and CT3 part (I do not solder CT2 parts), I hook it up to the serial USB to my PC and see the reading through serial connection in arduino.

1. Before I connect CT to the board, the reading CT3 shows an increasing amount of power, while CT1 shows normal reading around 0-4 Is there something I miss from the board? I have attached the screenshot below.


2. If I connect the CT to CT1 jack, I see an increasing amount in the reading, but when I pull out the jack, the CT1 reading does not revert back to zero and I have to turn off the board and turn it on again. Is this normal ?


Also what is the reading units? is that in mA ? The Board Voltage showing 3372 which I believe is 3.372 Volt and it shows correct reading.


Thanks very much for the help.


kind regards,


Sergegsx's picture

Re: emontx shows funny reading

I believe this is because when there is nothing connected to an analog pin this will fluctuate randomly. I think if you connect it to ground you will see it drops to zero, but please dont try it cause i dont know emontx board and dont want you to break anything.

But basically if an analog pin is not connected to something the readings are just random noise.

Connect the CT and if it reads correctly then forget about it.

jkoe888's picture

Re: emontx shows funny reading

thnank youu I'll try that..

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