After some more research: the 403 disables the optical sensor after 240sec.
It seems you can keep it awake (longer) by placing magnets around the optical head.
More info can be found here: https://gathering.tweakers.net/forum/li ... /1776625/2

Hi, Finally got the code working for me, but it only reads a few values when I activate the meter. When running the reading every minute (through a cron job), I only get 4 values after which I get None all the time. Does the Kamstrup 403 deactivate the IR port after 5 minutes, independent of reading ...