How to Measure voltage for each phase + emoncms local to remote

Hi there,
I have two doubts

1)How do I measure voltage per phase in a three phase system. The three phase resource page says that emonTx acts like a watt meter. hence a part of ct sensor and one ac-ac adapter provides current and voltage respectively for one particular phase. My question is where do I physically connect the ac-ac adapter to get voltage of a phase (say red line), considering that I will be connecting the adapter to a plug point.
One of the reasons I am asking this is because v have rewired our office electricity supply in such a way that red line contains only light load, yellow line contains only plug load and blue line contains only aircon load. So there are three diff CT sensors on each wire to make sure individual current is measured. How do I go about measuring individual voltage per phase?

  1. The values that I update in emoncms local is being updated in emoncms remote. but the dashboards that I have created are not being updated in I need to create dashboards separately in emoncms/org as well. Is this how it is meant to be?
    emoncms local dashboard dashboard

with regards,

Because there is only one voltage input on the emonTx, you can only measure the voltage of one phase. Therefore, the voltages for the other two phases are an approximation to the true voltages. This is explained in the comments in the sketch - “POSSIBLE SOURCES OF ERROR”. Unfortunately, without designing and constructing your own hardware, or using three emonTx’s, there is no better way. You could, by trial and error, introduce a scale factor in the power calculations that would estimate the reduction in the power cause by the volt drop due to the loads, but unless your supply is particularly weak, it might not be necessary.

Your local emonCMS and the online are, once the data has been transmitted, totally separate, so you need to redo the setup you have in your local version into I believe the online version may be slightly different to your local one.

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