Smartmeter binding thing goes offline once in a while with bidirectional meter

I’m using an Raspberry Pi 2B with an USB-connection and installed openHABian and openHAB3.2 stable and the “volkszaehler” IR-readout.

Worked fine with my onedirectional meter until yesterday. I got a new bidirectional meter for use with my PV and it works also, but once in a while, the Thing goes offline with “wrong crc” and comes up again afterwards.

2022-03-15 16:33:43.909 [INFO ] [ab.event.ThingStatusInfoChangedEvent] - Thing 'smartmeter:meter:2Richtung' changed from ONLINE to OFFLINE (COMMUNICATION_ERROR): wrong crc
2022-03-15 16:33:51.313 [INFO ] [ab.event.ThingStatusInfoChangedEvent] - Thing 'smartmeter:meter:2Richtung' changed from OFFLINE (COMMUNICATION_ERROR): wrong crc to ONLINE
...
2022-03-15 16:37:43.935 [INFO ] [ab.event.ThingStatusInfoChangedEvent] - Thing 'smartmeter:meter:2Richtung' changed from ONLINE to OFFLINE (COMMUNICATION_ERROR): wrong crc
2022-03-15 16:37:50.981 [INFO ] [ab.event.ThingStatusInfoChangedEvent] - Thing 'smartmeter:meter:2Richtung' changed from OFFLINE (COMMUNICATION_ERROR): wrong crc to ONLINE
...
2022-03-15 16:39:43.920 [INFO ] [ab.event.ThingStatusInfoChangedEvent] - Thing 'smartmeter:meter:2Richtung' changed from ONLINE to OFFLINE (COMMUNICATION_ERROR): wrong crc
2022-03-15 16:39:50.960 [INFO ] [ab.event.ThingStatusInfoChangedEvent] - Thing 'smartmeter:meter:2Richtung' changed from OFFLINE (COMMUNICATION_ERROR): wrong crc to ONLINE

This happens exactly every two minutes, the Thing is configured like this:

UID: smartmeter:meter:2Richtung
label: Smart 2Richtung Meter
thingTypeUID: smartmeter:meter
configuration:
  mode: SML
  refresh: 5
  baudrate: AUTO
  conformity: NONE
  port: /dev/ttyUSB_smartmeter
  baudrateChangeDelay: 0

(same configuration as with the onedirectional)

changed the refresh to 10secs and it seems to settle. Is the 5secs interval with bidirectional meters to fast for the Pi2?

edit:
The “wrong crc”-errors are a bit more seldom, but they’re still here.

Is the bidirectional meter from the same manufacturer?
The reading with optical probe and a “platinencomputer” is a little fragile I would say.
There are many aspects which can lead to a crc error.
I would check following things:

  • the wire of the cables should not be too long and no bigger power cable should be in the nearer area.
  • check if the probe (head) is on the meter in the right angle on the smart meter (there are receive and transmit IR-LEDs which have to work together).
  • how many devices are connected to the USB Bus of your device? Maybe a limit is reached?
  • I heard some had better results with this “Globuli”: Mantelwellenfilter – Wikipedia

Maybe not for Pi2, but for the serial and optical communication to your smart meter in general? Smart meters are not known to have a big cpu :wink:
Do you really need the values in this fast interval?