How to categorize a bi-directional PV circuit?

[joacchim]

I have a grid-tied PV system that both sells to grid and draws from the grid to support my loads.  Is there an Emporia Vue CT or other device that will reflect the net between these two energy flows?  Right now it looks like if I characterize the circuit as solar, power flow in both directions is added as if all flow is to the grid, when actually some is coming in from the grid.  Any suggestions?

[John]

I too have a similar problem. I have a solar PV system connected to a sub-board. I monitor the complete sub board from the main board with the Vue CT. Sometimes it is generating power and sometimes it is consuming power (eg at night) but it seems the Vue App only allows it to monitor one way or the other? I’m not exactly sure how CT’s work but is there a way the power can be shown as either positive or negative (consumption or production)? It shows a value either way so is this something that can be sorted by the app? Thanks 🙂

[emporiacs]

Currently, the 50A sensors do not measure bi-directional power.  We are planning on implementing a firmware update that will make that functionality available on existing and new 50A sensors and therefore we recommend you install them per the installation guide so you will not have to make any changes to your existing configuration once it’s released.

When monitoring a solar/generation circuit, you’ll want to install the sensor with the arrow (K➜L) pointing towards the breaker.

More info: https://help.emporiaenergy.com/hc/en-us/articles/4408877088023-Solar-Monitoring

[daklein]

Emporiacs,    I would be interested to test this update to measure bi-directionally.  (I’m not sure I see neg power on my main 200A CTs either, when I think I should be seeing due to solar backfeeding the panel through a 50A CT circuit and there should be power also going out the 200A CTs on the panel main).   Thanks!

[emporiacs]

The Vue Gen 2  is capable of net metering solar generation. The 200A sensors that are included with the device are directional and can measure any energy that is generated in excess of your consumption – as long as the sensors are installed between your utility meter and the solar input to your system. You can check out our Solar Supplemental Guide for more details on how the device needs to be installed to monitor a solar system.

You can also use the 50A sensors that come with the Gen 2 bundle to measure the amount of energy generated by your solar system (this is not required for net metering, though). Once setup, your Vue Gen 2 will show excess net generation as green numbers and green bars on the graphs. Net consumption will display as blue numbers and bars.

More information

[scrambler]

@emporiacs Emporia has been promising the bidirectional update for years, is there some actual planned date for such an update, or is it just a wish?

Just would like to know the reality of it all…

Thank you

[Author]

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