The manufacturer of the chips says 100,000, but not guaranteed. Since the data memory is already constructed as a ring memory, the same blocks are described only once per run. Such a run can take 1 time per day to months, depending on the recording density. The meter readings are saved in a flash area every 1/4 h. In this case, however, 5 blocks are kept ready as fail-safe and automatically switched on in case of an error. So far, however, we have not had such a case within 5 years.