EM2GO Home: Workaround for old fw current and phase setting

[dniakamal]

We would like to you to consider the following PR as a workaround for the EM2GO Home charger to address the following issues:

• Ignores 0A current when starting -> Set minimum of 6A when starting.
• Always starts charging with 3 phases even if evcc is set to auto or 1 phase -> Read phase setting from lp send start charging and phase setting in a row to avoid 3 phases when 1 phase is requested. We need to read the value from the lp as the charger does not know the phases needed and always starts with 3p.
• Switch phases during charging -> stop charging, pause for 10 seconds, and start charging with changed phases.
  This PR tries to fix issues mentioned in EM2GO - Phasenumschaltung (EMH011AC1RW) #12382, em2go startet immer bei 11kW - PV Modus - Regelt nicht schnell genug - bricht ab #14307, EM2GO-Home Probleme mit (Modbus-)Verbindung & Phasenumschaltung #14488 and evcc & EM2GO-Home Wallbox & KIA EV6 - Lade- und Verbindungsabbrüche und keine Phasenumschaltung / aktueller Stand #14643.

The workaround should only apply, if the firmware is <1.3 which will be tested by sending a current setting of 6.1A to the charger. If the returned value is 6A, the firmware is <1.3. If the returned value == 6.1A then it is assumed, that the firmware is >=1.3.

[RenatusRo]

Does this
If the returned value == 6.1A
implicitly imply that the box can control the current in 100mA steps now?

[dniakamal]

Does this If the returned value == 6.1A implicitly imply that the box can control the current in 100mA steps now?

Yes that is correct, but not with the old fw version.

[RenatusRo]

Then there should probably be two different templates for the Home
to correctly reflect the "mA" capability depending on the FW version?
https://github.com/evcc-io/evcc/blob/master/templates/definition/charger/em2go-home.yaml

[dniakamal]

Then there should probably be two different templates for the Home to correctly reflect the "mA" capability depending on the FW version? https://github.com/evcc-io/evcc/blob/master/templates/definition/charger/em2go-home.yaml

For this purpose, we are setting "mA" capability in the charger golang file if the new firmware is installed:
`

if chargerCurrent == 6 {
	wb.workaround = true // Old FW installed
} else {
	wb.workaround = false // New FW installed
	maxCurrent = wb.maxCurrentMillis // This is setting "mA" capability
}

`

[RenatusRo]

which is nice.
but only a template can fix the documentation at
https://docs.evcc.io/docs/devices/chargers#em2go
otherwise the Home won't be listed as mA capable
which might be a major selling point - not my business though :-)
people use the https://docs.evcc.io/docs/devices/chargers for their buying decisions ...

[njd1893]

which is nice. but only a template can fix the documentation at https://docs.evcc.io/docs/devices/chargers#em2go otherwise the Home won't be listed as mA capable which might be a major selling point - not my business though :-) people use the https://docs.evcc.io/docs/devices/chargers for their buying decisions ...

Agree. That's how I found the EM2GO Home in the first place.

[dniakamal]

which is nice. but only a template can fix the documentation at https://docs.evcc.io/docs/devices/chargers#em2go otherwise the Home won't be listed as mA capable which might be a major selling point - not my business though :-) people use the https://docs.evcc.io/docs/devices/chargers for their buying decisions ...

Agree. That's how I found the EM2GO Home in the first place.

Very well. We have added mA capability in the template and set mA support in the charger when not using the workaround.
We keep two templates, em2go and em2go-home for now, for compatibility reasons where existing users are using the "em2go-home" template in their evcc.yaml.

[premultiply]

Should that not better be placed before enabling again?

[dniakamal]

Should that not better be placed before enabling again?

In general you are right, but the chargers old fw is always starting with 3p, even if we send the command in the first place. That´s why we first need to enable it, then set the phases, This is happening within 60ms, so it should not be an issue for the EV.