Help setting up Solar PV divert (EcoMode) on OpenEVSE WiFi

I am well behind you guys. I cannot get the openevse on my feeds?

How do I do that?

What hardware setup do you have?
Are you upgraded to the latest software/firmware?
What browser are you using?
My setup is an EmonPi on the same local network as the OpenEVSE and I used these settings:

I’m not saying my settings are optimum, but right now they work so I’m not fiddling with them. :smile:
Obviously, your IP address will be different from mine.
You will find the “Emoncms write-apikey*:” on the EmonPi web interface under Setup->My Account.
The default MQTT password is emonpimqtt2016.

I am using Safari to access

Emons low-write 9.8.28 | 2018.01.27 emonSD-26Oct17

EVSE Hardware 4.12.3.EU OpenEVSE WiFi 2.7.0

Did you have to do anything to set up the Emoncms Node to include openevse? You can see from my screenshot I do not have an openevse node at all? You have node : openvse amp in your screenshot.
Thanks

Once you have the correct parameters set up in the OpenEVSE, the openevse node should automatically appear in the “Inputs” page, updating every 30 secs.

Once you have that you can configure any of the items to log to feed.
Then they will appear in the “Feeds” page:

However, feeds are not required to make the “Eco” charging mode work.

Ok, thanks for letting us know. I have added a note to the readme:

and opened an issue:

Yes, as @ebsol said the OpenEVSE Inputs will appear in the Inputs page of Emoncms. You then need to log these inputs to feeds to record the data. See Emoncms logging input to feeds guide.

Thanks Glyn.

It was an almost perfect day for testing yesterday: :ok_hand:

Nice and easy to see the algorithm doing its thing. The car started ramping down the current around 1pm as it approached 100% SOC.

I notice that the algorithm is being a bit conservative by about 500W. Is there something I can set / adjust / calibrate to utilise that extra bit?. By the end of the day It represents several KWh.
I know, I’m just plain greedy. :grin:

All working now. Thanks!

I think the documentation should express the importance of making the connections (correctly!) in the EVSE charger wifi. I spent hours trying to get an openevese node on my emonpi not realising that it all falls in to place automatically when connections have been made.

Thanks for all your help!

Geoff

That’s great news! Hope you get some sun :sun_with_face:

Fantastic! Great to see it in action. All ready for spring now :smiley:

It should only be 100W less, it would be possible to remove this 100W buffer if you changed #define GRID_IE_RESERVE_POWER 100.0 to #define GRID_IE_RESERVE_POWER 0`

You would then need to compile and upload the WiFi FW to the ESP. I’m keen to keep this buffer in place to avoid inadvertently importing. Possible we could reduce it to 50W. There could also be some discrepancy added in from the fact the OpenEVSE does not measure the actual VRMS voltage (like the emonPi), it assumes 240V VRMS which may or may not 100% match your actual VRMS.

I zoomed right into the graph and it’s actually around 400W.

Next time I charge I will try with that definition changed to 0 and see what difference it makes.

Is “#define SERVICE_LEVEL2_VOLTAGE 240” the figure used during the calcs. If so, is it worth me changing that to 230, which is closer to the average vrms values I see in the EmonPi input?

Would it be practical to fetch the vrms from the EmonPi and use that rather than a fixed value. I guess there will be some voltage drop between where my ct clamps are and the OpenEVSE, but at least it will then be able to track any changes in voltage.

Yes, that’s the value which is used in the calcs. Good idea, it would be more accurate to make it 230V for your location. In my location the voltage is often around 250V.

As you can see from our comment in the code, it would be more accurate to use the actual voltage figure. The current OpenEVSE hardware does not support voltage monitoring, it would be possible to obtain the value from the emonPi/emonTx but this does add potential issues and another potential failure point. It’s something we’re considering for a future solar pv divert 2.0 update.

Feel free to experiment using VRMS from the emonPi. To do this the OpenEVSE would need to subscribe to emon/emonpi/vmrs.

Thanks for your help I got an ISP programmer.

Downloaded the the HEX file from here and renamed it open_evse.hex.
Bat file and eeprom_24.bin from OpenEVSE site and followed the instructions from the site.

all updated and now working

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