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

ebsol · 2018-03-18T09:43:15.991Z

glyn.hudson:

Same here, not a good day for solar. Lots of wind though, the UK grid was over 40% from wind today

Let me know how you get on when the sun comes out.

40%! wow that’s impressive

On a side note, I noticed that since loading 4.12.3.EU, the display starts to shimmer after a couple of minutes.
I’ve looked at the code and traced it to the timer used to provide the 2 minute forced display update required by the spec.
It’s just a missing line that updates the time variable each time it’s triggered. It’s inside loop() and should be:

  // Force LCD update (required for CE certification testing) to restore LCD if corrupted.
  if ((millis()-lastlcdreset)>120000) 
  {
    g_OBD.Update(OBD_UPD_FORCE);
    lastlcdreset = millis();  // <--- MISSING LINE
  }

I haven’t done any sort of collaborative code before, so I’m not sure what I should do. Do I just report it here or should I sign up for a github account and contribute it there somehow?

glyn.hudson · 2018-03-18T10:30:52.864Z

ebsol:

On a side note, I noticed that since loading 4.12.3.EU, the display starts to shimmer after a couple of minutes.

I’ve looked at the code and traced it to the timer used to provide the 2 minute forced display update required by the spec.

It’s just a missing line that updates the time variable each time it’s triggered. It’s inside loop() and should be:

// Force LCD update (required for CE certification testing) to restore LCD if corrupted.
if ((millis()-lastlcdreset)>120000)
{
g_OBD.Update(OBD_UPD_FORCE);
lastlcdreset = millis(); // <— MISSING LINE
}
I haven’t done any sort of collaborative code before, so I’m not sure what I should do. Do I just report it here or should I sign up for a github account and contribute it there somehow?

Oh good spot. ~~I’ll fix this~~

Done: please could you try the latest release vD4.12.3.EU1 which includes the fix: Release 4.12.3.EU1 · openenergymonitor/open_evse · GitHub

I’ve marked this as a pre-release, I will do thorough testing on Monday when I’m in the lab. Thanks for reporting.

FYI: The usual way to report an issue is via github issues or if you wanted to submit a code request change the usual way is a github pull request.

glyn.hudson · 2018-03-18T10:33:40.092Z

ebsol:

I think I remember reading somewhere that the code is very large and so the bootloader had to be removed to make room

Correct, this is exactly why. Also the openevse team did not want to make it too easy to change the openevse FW since it has important safety controls.

Pukka:

I understand the flash.bat file and that i need to replace the open_evse.hex with your version but do i need the eepron_24.bin?

The eepron_24.bin is just the openevse config. I would skip flashing this to use the default config.

Pukka:

also can i just connect the openenergy programmer to the FTDI serial?

Yes, you can use this to read the serial and provide DC 5V power to the board, but an ISP programmer will need to be used to flash the open_evse FW.

ebsol · 2018-03-18T10:57:22.707Z

glyn.hudson:

Done: please could you try the latest release vD4.12.3.EU1 which includes the fix:

Yup, the shimmer effect has gone now. Thanks.

glyn.hudson:

FYI: The usual way to report an issue is via github issues or if you wanted to submit a code request change the usual way is a github pull request.

Thanks, I will look into that for next time.
After pestering you with my dumb questions, it feels good to be able to contribute something back.

glyn.hudson · 2018-03-18T20:59:36.919Z

ebsol:

Yup, the shimmer effect has gone now. Thanks.

Great, good to hear.

ebsol:

After pestering you with my dumb questions, it feels good to be able to contribute something back.

Indeed, thank you very much . It’s not pestering, any questions you have usually indicate a lack of documentation/explanation on our part.

ebsol · 2018-03-19T15:04:38.655Z

Yay! Was blessed with some sun beams today, so was able to test it. It’s definitely doing something

Eco_Working798×900 91.6 KB

I didn’t start logging the OpenEVSE amps until after I started, so missed some at the beginning.
The solar was pretty erratic, so it was a harsh first test, but I’m certainly pleased with the results.

glyn.hudson · 2018-03-19T17:33:09.322Z

ebsol:

Yay! Was blessed with some sun beams today, so was able to test it. It’s definitely doing something

Yeah! That’s working perfectly

ebsol:

I didn’t start logging the OpenEVSE amps until after I started, so missed some at the beginning.

The solar was pretty erratic, so it was a harsh first test, but I’m certainly pleased with the results.

The charging rate is adjusted every 10s in 1A increments so it will track the solar PV output very closely.

ebsol · 2018-03-20T17:22:48.995Z

Thanks Glyn. Got some more ev changing in today. Still working great.

glyn.hudson:

…sorry to hear it’s not working on IE 11…

glyn.hudson:

…any questions you have usually indicate a lack of documentation/explanation on our part…

I think, for sure the docs should strongly discourage using IE as it’s not currently supported.
If you just take the Session Status box, using my Apple iPhone or Android tablet, It instantly updates from “Not Connected” to “EV Connected” to “Charging” as it should. But with IE, no matter how much I try to refresh the page the status never changes. It’s the same with Windows 7 and 10.

I’m pretty sure if I’d known about this before, following your doc would have got me up and running without any problems.

FatJuan · 2018-03-21T10:30:39.606Z

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

no%20evse2546×882 201 KB

How do I do that?

ebsol · 2018-03-21T16:53:37.218Z

FatJuan:

…I cannot get the openevse on my feeds?

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:

Energy295×599 31.4 KB

Mqtt292×750 36.8 KB

I’m not saying my settings are optimum, but right now they work so I’m not fiddling with them.
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.

FatJuan · 2018-03-21T18:26:52.802Z

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

ebsol · 2018-03-21T21:16:59.050Z

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:

Image912×936 36.1 KB

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

glyn.hudson · 2018-03-22T00:31:27.979Z

ebsol:

I think, for sure the docs should strongly discourage using IE as it’s not currently supported.

If you just take the Session Status box, using my Apple iPhone or Android tablet, It instantly updates from “Not Connected” to “EV Connected” to “Charging” as it should. But with IE, no matter how much I try to refresh the page the status never changes. It’s the same with Windows 7 and 10.

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

github.com/OpenEVSE/ESP8266_WiFi_v2.x

Add note to suggested not using IE 11 or earlier

committed 11:51PM - 20 Mar 18 UTC

glynhudson

+2 -0

and opened an issue:

github.com/OpenEVSE/ESP8266_WiFi_v2.x

IE 11 Compatibility

opened 11:48PM - 20 Mar 18 UTC

closed 01:22PM - 16 May 18 UTC

glynhudson

bug

Issues with updating info (info / status does not update) been reported with IE …11. I don't think IE compatibility is that important since I doubt many users will be using (or should be using IE!). However if it's an easy fix it would be worth doing. Everything seems to work fine with Edge. There are the issues reported with IE: From: https://community.openenergymonitor.org/t/help-setting-up-solar-pv-divert-ecomode-on-openevse-wifi/6859/19 I've added a note to the readme to suggest use of IE is not recommended.

FatJuan:

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

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.

ebsol · 2018-03-22T09:22:38.901Z

Thanks Glyn.

It was an almost perfect day for testing yesterday:

charging1104×515 38.6 KB

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.

FatJuan · 2018-03-22T11:15:17.139Z

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

ebsol · 2018-03-22T13:01:48.508Z

FatJuan:

All working now. Thanks!

That’s great news! Hope you get some sun

glyn.hudson · 2018-03-22T23:40:44.133Z

ebsol:

It was an almost perfect day for testing yesterday:

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

ebsol:

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?

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`

github.com

OpenEVSE/ESP8266_WiFi_v2.x/blob/master/src/divert.cpp#L32


      
          
          // Or modulate charge rate based on on excess power (if grid feed (positive import / negative export) is available) i.e. power that would otherwise be exported to the grid is diverted to EVSE.
          // Note: it's Assumed EVSE power is included in grid feed e.g. (charge rate = gen - use - EVSE).
          
          // If EVSE is sleeping charging will not start until solar PV / excess power > min chanrge rate
          // Once charging begins it will not pause even if solaer PV / excess power drops less then minimm charge rate. This avoids wear on the relay and the car
          
          #define GRID_IE_RESERVE_POWER   100.0
          
          // Default to normal charging unless set. Divert mode always defaults back to 1 if unit is reset (divertmode not saved in EEPROM)
          byte divertmode = DIVERT_MODE_NORMAL;     // default normal mode
          int solar = 0;
          int grid_ie = 0;
          int min_charge_current = 6;      // TO DO: set to be min charge current as set on the OpenEVSE e.g. "$GC min-current max-current"
          int max_charge_current = 32;     // TO DO: to be set to be max charge current as set on the OpenEVSE e.g. "$GC min-current max-current"
          int charge_rate = 0;
          int last_state = OPENEVSE_STATE_INVALID;
          uint32_t lastUpdate = 0;
          
          
          double available_current = 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.

ebsol · 2018-03-23T00:22:52.075Z

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.

glyn.hudson · 2018-03-23T00:40:40.549Z

ebsol:

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?

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.

github.com

OpenEVSE/ESP8266_WiFi_v2.x/blob/master/src/divert.cpp#L120


      
          {
            Profile_Start(divert_current_loop);
          
            Profile_End(divert_current_loop, 5);
          } //end divert_current_loop
          
          // Set charge rate depending on divert mode and solar / grid_ie
          void divert_update_state()
          {
            Profile_Start(divert_update_state);
          
            StaticJsonDocument<128> event;
            event["divert_update"] = 0;
          
            if(mqtt_grid_ie != "") {
              event["grid_ie"] = grid_ie;
            } else {
              event["solar"] = solar;
            }
          
            // If divert mode = Eco (2)

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

Pukka · 2018-03-30T13:38:22.020Z

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