question

nhuillard avatar image
nhuillard asked

EV Charging Station: wrong power displayed, not updated

The EV web interface does not show the correct power drawn by the vehicle. It also does not always update the power when manually changing current. This leads to wrong energy counting...

This is pretty obvious in VRM: when starting/changing the EV charging, the total power drawn from the grid does not reflect the power drawn by the EV.

Ex.: before the Victron EV Charging Station, I used a 8A socket with an old grid meter, which shown ~1840W and ~1810VA, whereas now with the EV Charging Station at 8A, the reported power is more like 1600W (while the grid input reflects the ~1800W). 6A reports ~1200W when it looks more like 6A×230V=1380VA or W.

I read somewhere else that I could enroll in beta-testing the EV Charging Station, which I own since a few months now. This would be nice ;-)

ev charging station
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

11 Answers
nhuillard avatar image
nhuillard answered ·

@Lucian Popescu (Victron Energy Staff) just finished investigate my system. The thing is that the current EVCS hardware does not measure the voltage, and uses a static value instead. Lucian changed this value to a more realistic one on my setup.

I suggested that the EVCS uses the AC voltage it can get from the GX system, if connected to it, and fallback on the static value if the EVCS is really stand-alone (I'm thinking that there should not be many Victron EVCS outside of Victron systems, and without a GX device...)

I'll check this week-end if the reported power is more accurate.

The remaining issue is that the power is not always updated when the current changes... I'll check that too, but I guess it won't be solved without a firmware update.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

robo9 avatar image
robo9 answered ·

Hello nhuillard

I have the same problem. The W displayed does not match the Wh actually consumed.


https://community.victronenergy.com/questions/154095/ev-charging-station-wrong-power.html?childToView=154991#answer-154991

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Lucian Popescu (Victron Energy Staff) avatar image
Lucian Popescu (Victron Energy Staff) answered ·

Hi, what is the firmware version that you are running on the charging station?

1 comment
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

nhuillard avatar image nhuillard commented ·

V3.3/1.22 SN: HQ2207DJGRT

I regularly check the firmware updates of all the devices I have here, as I know there will be improvements.

I can also invite you to my VRM system if need be.

0 Likes 0 ·
robo9 avatar image
robo9 answered ·


Firmware-Version 1.22
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Lucian Popescu (Victron Energy Staff) avatar image
Lucian Popescu (Victron Energy Staff) answered ·

if you both can give me the VRM porta ID's I can have a look. Can you please send me an email with the ID? lpopescu@victronenergy.com


2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Lucian Popescu (Victron Energy Staff) avatar image
Lucian Popescu (Victron Energy Staff) answered ·

@Robo9 I'm writing here so other users can see this, Renault ZOE is not charging below 10A, Soon, a minimum current option will be aded, and that should solve the issue.

5 comments
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

nhuillard avatar image nhuillard commented ·
Here, the ë-C4 (Stellantis e-CMP platform) charges from 6A to 16A (didn't check above), at 2A steps, ie. 7A is apparently the same as 6A, while 8A is ~480W more.
0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image Lucian Popescu (Victron Energy Staff) ♦♦ nhuillard commented ·

Your unit was calibrated as requested, maybe we shoud add a calibration method available for the users? what do you think?

0 Likes 0 ·
nhuillard avatar image nhuillard Lucian Popescu (Victron Energy Staff) ♦♦ commented ·
Thank you for your time and settings!

I'd say that a manual voltage calibration would be nice, as a first step, or if using the GX actual voltage is really not possible as described below.

0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image Lucian Popescu (Victron Energy Staff) ♦♦ nhuillard commented ·
That's just adding more complexity for the device, and that's something we are avoiding. The charging station is not a measuring device, at least not for this version.
0 Likes 0 ·
nhuillard avatar image nhuillard Lucian Popescu (Victron Energy Staff) ♦♦ commented ·

Since the EVCS web interface displays power, energy, cumulated energy, and even cost and saved cost, it'd rather be correct ;-)

Manual calibration would be a plus.

Using the AC voltage from the GX, if available, would be definitely cool. Since it already gets a lot of info from the GX to enable automatic mode, it shouldn't be a nightmare.

I'm ready to wait ;-)


0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image
Lucian Popescu (Victron Energy Staff) answered ·

"power is not always updated when the current changes... I'll check that too, but I guess it won't be solved without a firmware update. " I don't know anything about that, can you send me a video?


1 comment
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

nhuillard avatar image nhuillard commented ·

This is a screnshot from the VRM: the power increase at 15h40 was due to changing the EVCS current from 6A to 8A.

capture-decran-de-2022-09-09-19-18-52.png

The power increase is reported on both "AC Consumption" and "EV Charger Power", but I changed the current back to 6A a few minutes later. The AC Consumption graph shows the lowered power, but the EVCS graph does not. I had to disable then re-enable charging (hence the drop of both graphs at 17h12), for the reported power to be updated on the EVCS graph/GX console/web interface.

This does not occur all the time. It seems to occur more often when the current change is low (+/- 2A) vs. high (eg. 6A to 12A).

The various peaks before 17h12 and attempts at updating the power by changing the current (6 to 8A and 6 to 10 or 12A at 16h48).

The natural variation of the other loads at this time was low (200W max).

0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image
Lucian Popescu (Victron Energy Staff) answered ·

That's strange. Is it the same on the screen of the device? or just VRM?


2 comments
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

nhuillard avatar image nhuillard commented ·
Yes: it's the same on the device screen (checked a few times only), on the device web interface, in the GX Console and in the VRM (I compared those 3 many times).


They all agree, which is good ;-)
0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image Lucian Popescu (Victron Energy Staff) ♦♦ nhuillard commented ·
ok, good to know, thanks!
0 Likes 0 ·
nhuillard avatar image
nhuillard answered ·

Thanks to @Lucian Popescu (Victron Energy Staff) the "wrong power" part of the problem is largely solved (for me). It requires a calibration of the EVCS, done remotely by Lucian last friday.

Here is a test I did last evening:

capture-decran-de-2022-09-14-18-47-26.png

The power displayed are correct enough for me.

I happen to be part of a national test for EVs charging consumer habits; in this context, I have a measurement device for the whole house and for the EVCS, and can extract the actual measurement done by that device. See the LibreOffice sheet below, with some calculations to compare to data within the VRM.

T201_220914_030459.zip

What I can gather from this is:

  • the power reported by the EVCS is good, when taking the current it displays
  • the current itself is a bit wrong: when setting the charge at 10A, the EVCS reports 10.0A (note the decimal .0 part), but the actual current is 9.5A
  • this may be because the voltage here is higher than normal (239V), but the car decides that 10A must be 2250W (probably because the reference voltage should be 225V?), and thus draws 9.5A, which at 239V, makes ~2250W
  • the current (and voltage) fluctuates a bit, at least more than the EVCS/VRM reports: that flat power sounds like the other part of the problem "power not udpated" (sometimes a long time after the current was manually changed)

The next problem may be that the reported current (with a decimal digit as displayed in the GX console: 10.0A) is arbitrarily rounded to the expected current manually set (10A), which is not correct (should be 9.5A in my case).


2 comments
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

andreas-siebenmorgen avatar image andreas-siebenmorgen commented ·
I can confirm that the same issue is happening on my device using Firmware 1.21.

Changing charge current during charge is not calculated correctly afterwards.

Albeit I am a little “shocked“ to read that charging station is not measuring voltage. That is truly not to be expecdet for a device with that really premium price point :-(

So how can I fix the wrong reading on my EV charging station?

0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image Lucian Popescu (Victron Energy Staff) ♦♦ andreas-siebenmorgen commented ·

@Andreas Siebenmorgen please update the unit the to latest version, we have already released version 1.23, so yours is 2 versions old. Then, if the measurement is still not good enough, there is a power calibration function 1663772303438.png

0 Likes 0 ·
1663772303438.png (117.8 KiB)
andreas-siebenmorgen avatar image
andreas-siebenmorgen answered ·

Still the same.

Upgraded to 1.23, calibrated.

Reduced charge rate from 10A to 8A, but shown charging power is not lowering.

162c4bb1-bee5-453c-9b69-8da87214c9c7.jpeg

2803ed2d-3881-49ff-b2ee-3fb672b8b5a6.jpeg


After stopping and starting again, charge rate is shown correct:

969b79fe-163a-463a-9310-34d7bb6dff42.jpeg


2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Lucian Popescu (Victron Energy Staff) avatar image
Lucian Popescu (Victron Energy Staff) answered ·

Thanks @Andreas Siebenmorgen, that's already reported, and it will be fixed

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.