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My next problem is temperature measurement. Foccci seems to want an NTC, but my socket probably has a PT1000 installed.

Very good data. This means, the charger has half a minute delay between the physical voltage on its DC pins and the reported voltage in the communication. Or do I interpret the time axis wrong @johu?

muehlpower wrote: ↑Tue Jan 06, 2026 12:15 pm My next problem is temperature measurement. Foccci seems to want an NTC, but my socket probably has a PT1000 installed.

We can add PT1000 in the software. Further tracking in github issue https://github.com/uhi22/ccs32clara/issues/64

@muehlpower Just check the resistance on your socket at two different temperatures, to confirm the PT1000.

muehlpower wrote: ↑Tue Jan 06, 2026 12:15 pm temperature measurement.

Note current Foccci does not do anything but spit it out in spotvalues. (please correct me if things moved on since I last looked)

uhi22 wrote: ↑Tue Jan 06, 2026 12:39 pm do I interpret the time axis wrong

The time is much shorter; the entire log was about 10 seconds.

Clara/Foccci is limiting the charge current with increasing port temperature. https://github.com/uhi22/ccs32clara/blo ... ce.cpp#L90

Is it possible to use Foccci with 800V architecture? I know older chargers have 500V limit but is it just hardware problem or newer protocol like ISO 15118-20 is also needed?

Should work as is because we are already using Alpitronic

The sensor appears to be a PT1000. I can measure 1090 ohms at room temperature, and after placing it in 40° water, it was 1155 ohms. With the 12-bit ADC, this results in 84 digits in the range from 0° to 70°. This is not optimal; a lower-resistance pull-up would be better.

A PT1000 seems to be the rule rather than the exception.

https://www.te.com/de/products/connecto ... =pgp-story
http://de.evsegroup.com/150a-200a-ccs-t ... s-product/
https://www.phoenixcontact.com/de-lu/bus-inlets
https://www.sailtran.com/products/EV-ch ... ocket.html

muehlpower wrote: ↑Tue Jan 06, 2026 12:06 pm I have made further attempts. When I take the DC voltage from the charger output, it works. I think the problem is checking the difference in connection with a time offset!

To tolerate the time offset between the pyhsical voltage and the EvsePresentVoltage, added a two-seconds tolerance in the software.

Binaries: https://github.com/uhi22/ccs32clara/act ... 0752458118
Github issue: https://github.com/uhi22/ccs32clara/issues/52
Github commit: https://github.com/uhi22/ccs32clara/com ... cf9b11a9f9

Ready for tests @muehlpower

muehlpower wrote: ↑Tue Jan 06, 2026 2:46 pm A PT1000 seems to be the rule rather than the exception.

Created issue for further tracking the TP1000 topic: https://github.com/uhi22/ccs32clara/issues/64

(Edit) First implementation of PT1000 available:
https://github.com/uhi22/ccs32clara/act ... 0755353494
Added a new parameter TempSensType, to select either NTC or PT1000.
This version is completely untested. Ready for test @muehlpower

maciek16c wrote: ↑Tue Jan 06, 2026 2:00 pm Is it possible to use Foccci with 800V architecture? I know older chargers have 500V limit but is it just hardware problem or newer protocol like ISO 15118-20 is also needed?

It is not really clear. If I remember correctly, the DIN70121 is 500V. It is not clear, whether this is a fact or a rumor. The protocol implementation does not have a voltage limit at all. Foccci/Clara use the DIN spec as default. It depends on the charger, whether it allows more than 500V also with DIN. I'm not aware, that somebody tested this scenario, so we need a volunteer

I will try it but first have to find the problem with communication to the charger. Btw, is anyone working on ISO2? I found interesting repository with ISO2 decoder: https://github.com/EVerest/libcbv2g

New software available
https://github.com/uhi22/ccs32clara/act ... 0757491339
which attemts to improve the following three topics:
1. Time tolerance of voltage plausibilization
2. PT1000 support
3. Logged voltages in case of deviation between physical and logical voltage were factor 32 wrong.

Ready for test @muehlpower

Seems to be working. The log is again about 10 seconds long and also shows the voltage curve when I press the cancel button to stop it.

It's interesting that when I plug it in and wait a little while before starting the CCS charger, i.e., when the 5% comes later, charging doesn't work. Also, I've never managed to do a firmware update via the CAN adapter. It starts, and after 10% of the bar is filled, the connection breaks. Then the only thing that helps is ST-link. Am I doing something wrong?

My last post referred to 44.116. Now I have tried 44.119. Pt1000 with 1000 ohms shows:

Improved software: https://github.com/uhi22/ccs32clara/act ... 0760825425
It treats the unconnected temperature sensor 3 as "invalid", which means -50°C, so it does not hurt the max temperature.

The big deviation (64°C in the picture versus expected 0°C with 1000ohms) needs more analysis. To understand the issue, I added two spot values
temp1Adc and temp1Resistance. What do they show when connecting a 1000ohm resistor? We may have a tolerance problem with the pull-up, or a ground shift problem, or something else.

Try with 44,121. I connected to temp3 1k, 1k2, and 1k5. 1k ->25.3°, 1k2->76.2°, 1k5->155.1°. temp1 and temp2 are connected to the real sensors at approx. 22°. The intervals look good. The two built-in sensors have at 22° 1087 ohms and 1088 ohms, measured at the disconnected plug from the Foccci, i.e., with the entire cable to the CCS socket. This fits exactly to 22.5°.

muehlpower wrote: ↑Tue Jan 06, 2026 6:49 pm Also, I've never managed to do a firmware update via the CAN adapter. It starts, and after 10% of the bar is filled, the connection breaks. Then the only thing that helps is ST-link. Am I doing something wrong?

Are you running 500k baudrate?

Confirmed the wrong ADC values for the temperature inputs on my desk. Further discussion in the developer thread https://openinverter.org/forum/viewtopi ... 749#p88749

johu wrote: ↑Wed Jan 07, 2026 5:52 am Are you running 500k baudrate?

yes

Regarding update via web interface: make sure, that you are flashing the bin file, not the hex file. But also on my side, the update via web interface crashes with a probability of 10 to 30%. Usually the first time per day works fine. Not a satisfying situation.

uhi22 wrote: ↑Wed Jan 07, 2026 5:58 pm make sure, that you are flashing the bin file

I used the bin file.
Doing it with the ST-Link is no big deal. I do the same with the drive unit. To do this, I ran a connector with the appropriate pins to the outside.