EmonCMS & OpenEVSE with split phase power

I recently got my Emonpi working with a split phase powered home and solar. Now trying to get my EmonPi/EmonCMS & OpenEVSE to communicate so that I can charge my EV using the Solar PV divert mode (charge from solar power only).

I’ve been reading quite a bit, but still have a few basic questions below to get started.

Question # 1.
Which setup should I follow, there are setup instructions on both the openenergy page and openevse page?


Question #2.
Can I log everything locally (EmonCMS and OpenEVSE), or do I need to log locally AND remotely if using EmonCMS & OpenEVSE together?

I read this on the setup page but not clear to me. I’m a very beginner at this, but it seems that MQTT is being used now with my EmonPi/EmoCMS logging locally with no problems.

Emoncms Server Setup OpenEVSE / EmonEVSE Setup Guide - Guide | OpenEnergyMonitor

Emoncms server (HTTP) and MQTT both post the same status updates. Emoncms server and MQTT should not be connected to the same emonPi, since this will result in duplicate data. However, it is possible to use MQTT to post data to a local emonPi and Emoncms to post to a remote server e.g emoncms.org.

Question #3 (Grid measurement or PV measurement)
If I want to use the solar PV divert mode with Open EVSE, can I setup my EmonPI / EmonCMS, to read only grid import/export (power 1 is negative then exporting power and start charging) or do I need to setup the OpenEnergyMonitor Solar PV monitor??

SolarPV-gen topic

Grid (+I/-E) topic (If I use this topic, can I forgo monitoring solar generation)

Note: Since I am using an EmonPI with only 2 CT inputs (both being used to measure grid power in a split phase system

The OpenEnergyMonitor guide looks to be a bit more up-to-date and cover the complete end-to-end setup.

You can do either up to you, remote logging is not required.

Yes, that works fine

Yes, that is the recommended way of setting up the divert, no need to explicitly measure the solar generation.

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Thank you Jeremy for the info. Hopefully will get me going in the right direction :slight_smile: