Comm Required on some public slow chargers?

[JsonJason]

Hi openinverter forum, first time writing at here since getting large help of infos from here at building my own j1772 to 220v outlet adapter.(just a resistor and a diode on cp pin)
I have realized that some public slow chargers requires a plc communication to charge (even tho its not a ccs!),
so the choice of chargers has been getting smaller and smaller for me as the time goes.

some does not care and closes contactors immediately when it's plugged in, some does close contactors but opens after 1 min(and also says waiting for comms), some straight out refuses to close at all and rejects.

it feels like it's wanting a full blown plc comm.. and been looking at some options like foccci, ioniq CCM, and Homeplug adapters on
https://github.com/uhi22/pyPLC/blob/mas ... ardware.md
foccci is amazing but feels like quite an overkill for my application, ioniq CCM is not rly on the open market over here and Homeplug adapters also applies same to that.
But i did find a gridwiz peppermint on sale which, only 1 thread about it is on this forum.
So well, i'd want some informations and suggestions regarding to my application. Do i try to source the Hompelug adapters or CCM? or straight out build the foccci only to use it on non-ccs plugs?

[tom91]

I have realized that some public slow chargers requires a plc communication to charge

No they dont (some tesla units do), they require the sequence to be right. So you cannot go in with the values for requesting "charge" via your "dumb" adapter right away.

You need to follow the propper signal standard as described in the J1772 protocol. https://openev.freshdesk.com/support/so ... -sae-j1772

[JsonJason]

I'll try to do that, State B on plugin and flip of a switch then State C. but i did hear about the news on some chargers getting a PLC with it for some stupid reason(preventing fire from limiting the charge to 85%) and previously working charger that did not care with stupid charger not working after a software update on the charger. will try to see bout that later

[JsonJason]

also so far the only country that does these thingy with the slow chargers is my country only, south korea.
this is so stupid and pointless...

[muehlpower]

The question is not entirely unreasonable. According to the "Alternative Fuels Infrastructure Regulation", which will come into force on February 8, 2026, only AC charging stations that support PLC may be newly built in Europe. This does not necessarily mean that they will not also work with PWM, but backward compatibility is not mandatory, so there will be fewer and fewer conventional AC charging points.

[JsonJason]

I do already think quite most of the chargers here are not backwards compatible.
except some old ones that really does not have any PLC inside, most of them get updated and gets the backwards compatability removed

[jrbe]

I do already think quite most of the chargers here are not backwards compatible.
except some old ones that really does not have any PLC inside, most of them get updated and gets the backwards compatability removed

That sounds intentional. You mentioned something about fire, I wonder if they are intentionally removing the simple hack way of enabling them because of that.

[johu]

Which OEM cars even support PLC comms for AC charging?

[muehlpower]

Which OEM cars even support PLC comms for AC charging?

I asked myself the same question and googled it. The AI says my e-Golf could do it.
And for my 1950 Mercury, I'm hoping for uhi22's programming skills.

[JsonJason]

"normal" EVs are charging without any problem on the charging spots that my resistor diode setup fails, so far saw Tesla, Ioniq 5 and etc.
I wonder what hardware I will need to test it,like ordering foccci with only the essential parts?(Modem, supporting components and STM?)

[uhi22]

I have never seen AC charging using PLC, and cannot imagine that it will replace the PWM method. But I'm open to learn.
- Do you have an oscilloscope? Measure the CP pin.
- Does the charger have a cable with plug, or a socket without cable? In the second case it wants to see also a valid PP resistor to know the cable current limit.
- Foccci and pyPLC do not support PLC AC charging at the moment. If you like some experimentation, you could run either pyPLC with homeplug adaptor or Foccci to pull some log files. Based on such log files, we can find out how difficult it is to implement this feature. In best case, the good old DIN70121 is used, then the story is easy. In worst case, a late ISO15118 is used, where they force encrypted communication, which is a little bit out of reach from my point of view.

[JsonJason]

Currently, I don't have any osiloscopes but i have a friend to borrow one.
and the chargers that i have tried is all cable with plug.
for the focci, i can skip the contactor drivers and some unnecessary ICs and order with only STM and qca + some supporting components only?
because the homeplug adaptors are.. quite hard to find here

[uhi22]

Yes, contactor driver and lock motor driver can be skipped. Be careful regarding the Foccci version, the latest commit is an "intermediate" version, I recommend the last stable.

[JsonJason]

Yes, contactor driver and lock motor driver can be skipped. Be careful regarding the Foccci version, the latest commit is an "intermediate" version, I recommend the last stable.

thanks for the useful info, I'll probably use the 3aef7c9 commit then.... or 2cc0fae

[uhi22]

Yes, this makes sense

[JsonJason]

I have borrowed an osiloscope, and have tried quite some chargers(10 different brands), and i have managed to get all working.
I had to make a switch so i can switch the 1.3k resistance on and off the line.(many of them required it to go thru the states.)
Also, i have found a charger with PLC in it.

So well, I guess it ain't forcing cars to require PLC comm to charge...yet

[uhi22]

Does it apply 5% PWM together with the PLC? And does it fall back to higher PWM afterwards?

[JsonJason]

It always stays at 50%ish PWM and continues to stay like that with PLC.(Haven't got the foccci yet so no proper comm yet..)

[uhi22]

This looks like out of spec. For starting the high level communication with the car, the charger shall apply 5% PWM, and only then the car shall send the slac request. With 50% PWM the car shall use classic low level comm only.