EmonTX Shield in USA

[miq]

@Robert.Wall

So your “power” is the product of current and noise

Yeah that’s what I’m thinking.

[miq]

I’m looking at the other emonTx shield firmware on Github. If you don’t have your AC/AC wall adaptor plugged in, I think you better use this firmware:

https://github.com/openenergymonitor/emonTxFirmware/blob/master/emonTxShield/Shield_CT1234/Shield_CT1234.ino

And I think there is a section within the code where you have to change to suit your actual mains voltage, i.e change the 240.0 to actual Vrms in the US (120.0 AC).

  if (CT1) {
    emontx.power1 = ct1.calcIrms(1480) * 240.0;                         //ct.calcIrms(number of wavelengths sample)*AC RMS voltage
    Serial.print(emontx.power1);                                         
  }

[dpackham (Dave Packham)]

WAF rated 1-10

Wife Acceptance Factor
A 133" wide TV with a bunch of cables hanging out has a low WAF

[dpackham (Dave Packham)]

Hey I can post now. they limit new people to 19 posts a day and I hit my limit posting here. I am running the code above and it looks better. I will report back when i get the AC/AC adapter. is that USA bug that was fixed still in the other emonTXshield code?

[miq]

@dpackham

A 133" wide TV with a bunch of cables hanging out has a low WAF

Haha I see now [quote=“dpackham, post:24, topic:3257”]
is that USA bug that was fixed still in the other emonTXshield code
[/quote]

I think that bug is specific to emonTx V3 only , not for emonTx shield - well at least that’s what I understand from the code.
But once you have the AC/AC wall adaptor plugged in, you have to revert back to the first firmware you posted above.

[dpackham (Dave Packham)]

Will do. while waiting for the AC/AC i put the breaker box cover back on to maintain high WAF… on a scale of 1-10 im hovering around an 8 now so I need to keep things clean

ill ping this thread when I get the adapter

Thanks for your help here

[glyn.hudson]

@miq

I think in the firmware you’ve used, the real voltage is needed (sensed from the AC/AC wall adaptor), otherwise, the power calculation will yield the wrong result.

Correct, you’re using an emonTx shield which has totally separate firmware examples for Real Power (voltage & current) and Apparent Power (current only). The firmware update for the emonTx V3 does not affect the shield. If using the apparent power example on the Shield (without voltage sensor adapter) in the USA you will need set VRMS to 120V for each channel

https://github.com/openenergymonitor/emonTxFirmware/blob/master/emonTxShield/Shield_CT1234/Shield_CT1234.ino#L97

Using a voltage sensor adapter is highly recommended for increased accuracy.

@Robert.Wall

how do I tell the version?

That’s a “feature” of GitHub. I’ve never seen any understandable form of version control.

The emonTx V3 prints out it’s version number at startup:

EmontX V3 firmware releases can be found on the emontx3 github releases page, changelog (linked) provides more in depth info:

Releases · openenergymonitor/emontx3