question

kudos50 avatar image
kudos50 asked

Victron EV Charger cumulative charged kWh (total energy) on modbus

I noticed the forwarded energy counter is only for the "active session". The total energy counter from the EVCS internal website is not available on modbus yet. Are there any plans to make it available ?

Trying to the use EVCS to get some expenses back from my employer. The modbus connection works ok'ish for this purpose but for reporting to a csv on a schedule it would be far better if the total energy counter can be logged as well.

Modbus TCPev charging station
15 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

kudos50 avatar image kudos50 commented ·

Another reason for adding cumulative charged energy into the mix is that in its current state "overload protection", if hit hard enough, will stop the session thereby loosing the session counter data.

The car was charging last night but was not fully charged this morning. Most likely as DESS has charged the battery for a few hours, causing overload protection to kick in for too long ? Either way, session data is lost as the charger stops and needs manual restarting.

Setting autocharge will surely fix the car charging problem but will probably result in multiple sessions thereby depending on timely capture of the max value.

@Lucian Popescu (Victron Energy Staff) can you elaborate on overload protection timers causing the charging process to fully stop ?

0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image Lucian Popescu (Victron Energy Staff) ♦♦ kudos50 commented ·
In few words with example:

let's say you are charging with 15 A, overload is detected > it will reduce to 12A, overload again > it will reduce to 10A ........>6A. If the system still detects overload at 6A(minimum charging current), EVCS will stop and not restart.

1 Like 1 ·
kudos50 avatar image kudos50 kudos50 commented ·
In that case I guess I'm very very much in favour of having cumulative energy available on modbus. Considering charging does not restart, I guess load balancing is not "the same" as overload protection. So would be good to have loadbalancing that simply continues charging from suspendedevse once grid meter allows.
0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image Lucian Popescu (Victron Energy Staff) ♦♦ kudos50 commented ·
Or you can disable (at your own risk) the overload protection

Or you can create a custom setup in node red or any other platform that will take care of charging

It's impossible to have a perfect setup for all the systems in the world, that's why we allow external control.

0 Likes 0 ·
kudos50 avatar image kudos50 Lucian Popescu (Victron Energy Staff) ♦♦ commented ·
@Lucian Popescu (Victron Energy Staff) Can I interest you in the node-red flows that resulted from our overload discussion ? Not a good programmer but it works like a charm:
  • Read amps of the individual phases and determine which one has the highest load
  • Set max load per phase to 20A to prevent the future 3.30beta ESS peakshaving from running intervention
  • Check if NS is charging
  • Check if the other NS is charging (if true than cap outcome to 12A for master and 6A for slave)
  • Get current charging speed
  • If highest phase load > 20A, reduce charging speed
  • If outcome < 6A stop charging and start a delay timer
0 Likes 0 ·
kudos50 avatar image kudos50 kudos50 commented ·

Yes it is.... But re-using the flow I have in HomeAssistant for my Elvi will only ensure a full EV in the morning. I don't think the EVCS will accept 0A as input so anything below 6 will end up in a stop request. Not sure, but doing that may result in loosing session totals?
So the original request still stands. Please make the cumulative kWh from the web interface available on modbus as well :-)

Other than that I cannot integrate it with DESS easily. Whereas I know Dirk-Jan probably likes to get your charging numbers and consumption for his forecast and schedule at some point after 3.20 becomes available. Something I cannot possibly build in node-red. I'm a VRM user for DESS btw, not node-red.

0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image Lucian Popescu (Victron Energy Staff) ♦♦ kudos50 commented ·
Yes, cumulative kWh will be added in the next version
2 Likes 2 ·
kudos50 avatar image kudos50 Lucian Popescu (Victron Energy Staff) ♦♦ commented ·
@Lucian Popescu (Victron Energy Staff) I noticed you made modbus registers 5023 and 5024 available but I guess I could use some help interpreting them.

In my case the values are still low so only the numbers for 5024 are changing. But that number does not contain the same value as the number in the web interface.

For example, the web interface says 704.06kW for one of the units whereas 5024 only claims 4873. Please help.

0 Likes 0 ·
kudos50 avatar image kudos50 Lucian Popescu (Victron Energy Staff) ♦♦ commented ·
I'm probably missing something simple @Lucian Popescu (Victron Energy Staff) would you mind pointing me in the right direction ?
0 Likes 0 ·
Lucian Popescu (Victron Energy Staff) avatar image Lucian Popescu (Victron Energy Staff) ♦♦ kudos50 commented ·

(REG5023+(2^16) + REG5024)/100 = total power in kWh(float, 2 digits after point

0 Likes 0 ·
kudos50 avatar image kudos50 kudos50 commented ·
Thanks @Lucian Popescu (Victron Energy Staff) but I'm simply not good enough with number conversions I guess.
  • the EVCS has 1297,67 kWh on meter
  • low says 64230
  • high is reading 1

Google is normally my friend but with the various suggestions out there to get from uint16 to 32float I have been unable to figure this out.

Please help.


0 Likes 0 ·
Show more comments
0 Answers