I just read this European product brochure for a Mennekes EVSE (does the same function as the North American UMC). Interestingly, they have a temperature sensor built into the electrical plug. So it can reduce or interrupt charging if it senses the plug temperature getting too high. Maybe at some future time, Tesla should revisit their UMC architecture and implement something like actual temperature sensors rather than relying on flaky software algorithms to determine charging faults. http://messe.mennekes.de/fileadmin/user_upload/Downloads/Prospekte_UK/Charging%20cable%20mode%202.pdf
This is probably similar in implementation to the RAV4EV mod that protects the car from the bad J-handles melting the vehicle inlet. Honda Fit EV already has a sensor in the inlet to prevent such things. Tesla should absolutely do the same thing in the adapter. For example, when the temp hits a threshold, switch to a resistor that indicates the next step down in allowable current. Totally self-contained in the adapter.
This is actually the EVSE which Tesla Norway provides to customers when the customer's home charging grounding issues or voltage fluctuations (due to the fabulous Norwegian power grid) exceeds the Tesla UMC spec. I think I have the German version of this EVSE. Since it's limited to 13A, the cables are thin and light and much easier to handle on a daily basis, and the schuko-socket actually fits into public charging stations.
Interesting! Out of curiosity, can you summarize what the specific issues are with Norway's grid that caused so many problems?
One would think an NTC or PTC thermister in place of one of the resistors in the connection/button circuit might just do the trick for very little design time and $s.
- There's no ground/neutral from the utility to the subscriber - Tesla doesn't support the partcular 3-phase power distribution system which is most common in Norway - Electric heating is the norm here. Usually only attached single phase. Which can create large voltage fluctuations in the power grid in winter. - Tesla disconnects the 12V battery from the main battery when the charging port is open. This can deplete the 12V battery when charging in winter.
