I also tried to catch a signal with hall-effect sensor.
I even asked kindly to energy provider to replace the meter wtih recent version, because it makes an abnormal noise from time to time. But they won't (nothing to worry about).
Now I wonder if someone has an idea to log the meterings from such a meter (without writing it down

Hope to find a solution. My temperature and current loggings works like a charm (logs to mysql database and worked out with php).