I've been trying to read my smart meter through the P1 port (with success). However, digging through the P1 port specs, I noticed that the gas meter readings are only updated once per hour (since the gas meter only sends the readings to the electricity meter once per hour wirelessly). Since I wanted to use the gas readings to finetune my heating control system, that's as good as useless to me.
The gas meter does have an optical port, so I was hoping to be able to do more regular readouts through that. However, I can't find any indication of the protocol used anywhere. It seems the DSMR spec doesn't specify any port on the gas meter (only an optical P0 port on the electricity meter). Anyone every tried reading this port? The "product brochure" for the G350 does not mention the optical port at all.
I do have some other reservations on this approach:
- Perhaps the optical port is only active for a while after you press one of the buttons on the mater (to show the current value on the display)
- Reading the value more often might quickly drain the battery, the gas meter does not have any AC power
- The optical port might be password protected (ideally, reading values is not protected, but I'm afraid that everything will be protected)
If the gas meter was connected through wired MBUS instead of wirelessly to my E-meter, I might be able to break into that bus. However, it seems that there is no such connection present, at least I cannot access it from the outside.
A completely different approach would be to install a gas flow meter just before my boiler. Does anyone know of any flow meters that can be electrically read out? I did some googling, but I couldn't find anything that would work and was actually available for purchase to consumers in single quantities...