OpenEnergyMonitor Community

OpenEVSE Language Translation

Wow, great news.
I really appreciate your work, thanks!
I would like to order one. Just have some questions about the “other parts”…

Will the new kit differ very much from the currently available one?

I’m considering about to build my own OpenEVSE version, because I would like to measure the voltages of the 3 phases independenty, so I started to “redesign” your EmonTX Arduino Shield schematic, with 3 voltage inputs, and 4 CTs. I really like the OP-AMP modification, that I’ve found here, so I have integrated that solution also. On my test-PCB, it works very nice. (I’m really thankful about your great work, because from these things I could put together everything just in a few days) At the moment it’s only measuring 3 phase power, and the EVSE functionality still needs to be added. I use a Leonardo, which have enough IOs, so I think it can be managed, to have the measurement and the EVSE functionality together.

But reading your posts above, I started to afraid, that if the standards require special elements (because of the EVSE functionality), then it might be a difficult task to modify my schematic…

So I’m really looking forward to the new versions, kits, etc… :slight_smile:

You don’t want to kick off the old Atmega328, and use the 32U4, to make an improved, 3 phase compatible version, do you?

To tell the truth, when I read first, that you want to supply a “European version” of the OpenEVSE, then I was thinking, that you will replace the LCD (to the version, which supports the German/Hungarian/other EU characters), and also hoped, that the 3 phase (real) power measurement will be included.
(Don’t take it as a “reproach”, I’m really amazed by your work. I’m just giving you new product development ideas :slight_smile: )

Best regards,

The new unit will be identical to the current OpenEVSE kit that we sell. The only difference will be the type-2 socket instead of a tethered cable and three-phase option as well as full CE certification.

The EVSE currently only monitors current and assumes a unity power factor and a steady voltage. These assumptions are generally true with EV charging resulting in a a pretty accurate kWh reading, but I agree your solution would be more accurate at the expense of extra hardware. The three-phases should be balanced and at constant voltage when EV charging. If greater accuracy is required a billing grade meter can be installed inline with the EVSE.

I had been thinking about different language packs for the LCD. This would be quite easy to do since all the strings for the openEVSE are in a single file:

Feel free to translate the strings, I’m happy to re-compile the FW for different languages if required. However, I guess this would only be useful for the LCD menu. The new type-2 enclosure does not have a button since all interaction is done via the WiFi-gateway web interface. Currently translating the wifi-gateway interface would be more work since all the strings are not in a single file:

I have missed, that the button has gone :slight_smile:
At the moment I don’t know, that could it be a problem or not :slight_smile:

I did the translations (both the LCD and the WIFI), and that was the point when I realized, that the Hungarian characters are not supported (and I know, there is an EU-charset supported version of this LCD also). If you could manage to change the LCD (or, I don’t know, maybe the the firmware could be changed?) that would be a real success. Not only for Hungarians, but for German users also, I think. :slight_smile:

Unfortunately, here in Hungary, the electric grid is hmm… not too “uniform”. From street to street, house to house, the voltages are different. Even worse, if I take only my house, I measure, that the voltages of the 3 phases are different, varying from 220-248, easily.
There are a few PV installations nearby, having 1 phase inverters. If the sun is strong, and they are producing current into the grid, then the voltages are fluctuating to a large extent.

Moreover, the people that I know, and want “smart” EVSE, one reason of their decision is to measure the consumption. Precisely, because on the other hand, they put “charged into the battery” values oppose to the values from the EVSE. (They took that value from LeafSpy and other EV specific apps.)
If the values are “far” from each other, than a very long thinking is started :)))
It’s better, to present as “precise” kWh values, just as we can.

There is a product, which seems to meet these requirements:
however it’s not opensource.

My goal would be to make something similar, but without the fancy RGB LED ring, using an LCD, and connected to my emoncms :slight_smile:

However, if it would be a mobile/stationary capable solution (like the one on the URL), then it could be a really good product for the EU market.

As you can read Ready=“Keszenlet”, however, it should be “Készenlét”.


Ah nice work! I don’t think the character set is a hardware issue. I’m sure it could be fixed in software. Are you aware of any Arduino LCD libraries that support the character sets that you require?

At the moment, I think, it can not be solved by sw.
I downloaded the datasheet called “HD44780U (LCD-II) (Dot Matrix Liquid Crystal Display Controller/Driver)”
and it tells, that it has 2 versions:

and later, it shows the character tables also. I was able to display the marked character, so it’s pretty sure, that the LCD is the HD44780UA"00" version:

The datasheet shows the characters of the “02” hw. version, which are really the European chars:

I think, that the LCD firmware can not be replaced (I Google-d a lot about the firmware files, but couldn’t find any of them). What is you opinion?

By the way, the original OpenEVSE firmware has defined some special characters (for example the clock).
The LCD controller supports a few special character definitions. I tried to make own “é” character.
Basically it worked.
Unfortunately, if I used the “Language_default.h” file, and put the special char in a pre-defined constant (into the ROM of the Atmega), then not only 1 character, but some other “surrunding” (stored in the ROM) characters were also displayed. Just like if I would concatenate 2 char.constants.
I tried also the “print-out-function” solution, when not char-constants are used, but a function, which contains multiple print calls. That version worked, but it was uncomfortable, and I wouldn’t make all string>function conversions (also because there is not enough free special-character-space in the controller).

Ok sorry it looks like you may be correct with regard to the character sets. I know it’s possible to make the LCD display custom characters, but it would probably be too much work and take too much memory to make a custom character for each of your special characters

Unfortunately only 8 special characters can be defined.
And 5 or 6 is already “occupied” by OpenEVSE “icons”.

It would be very nice, if the LCD firmware would be replaceable…
But I’m afraid, it’s not…

Till now, I could not find any source for the A02 hw version.
I found some links, but wasn’t convinced, that it would be really equipeed with the European character set.

Yes, your totally right. I was wrong about the character set being defined in FW its actually in the hardware. It’s a shame the hardware with the correct character sets is not easily available. What’s the standard in Hungary for LCD characters? Do all character LCD displays use the correct character sets or do some just use the English character set? I.e is it acceptable to use the English character set to display Hungarian words (obviously not ideal).

:slight_smile: Yes, that’s what I have did. Display “Keszenlet” instead of “Készenlét”.
Not a big issue, just it would be nice to see correctly.
(just I hoped, that maybe you (the guys behind the OpenEnergymonitor webshop) will manage to replace the LCD with the EU version. :slight_smile: )

However, if you “accidentally” find somewhere a 44780U"A02" version LCD, available to purchase, please let me know :slight_smile:

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