Howto interface the Kamstrup Multical 602 to Home Assistant

Hardware
1

Dear Energy-monitoring wizards

I have a Kamstrup Multical 602 in my heating system and would like to read out as much information as possible into my Home Assistant setup.
It seems that my Multical 602 has many different interface boards [link] that you can attach to get access to the data with everything from InfraRed over M-bus to ZigBee and I am unsure which way to go.
Do all of these options present the same data?

I already have a ZigBee network (on HA with ZigBee2MQTT and Mosqitto), so this option seems compelling, but if M-bus is the better option I can also draw a wire between my HA and the Multical.

What do you guys have the best experience with? (Both choice of communication method, which hardware and sw support in HA)

Thanks for any leads.

BR David

2

You can’t read infra red as a permanent thing.

Pulse and M-Bus (wired and wireless) are the most common interfaces used. M-Bus obviously gives you more data than pulse counting.

You’ll need to have an external power supply on the 602 in order to read it frequently. Else the battery will be killed quickly.

Wireless M-Bus may not send that frequently (depends on module config)

No experience with Zigbee.

£25 posted if you need a wired M-Bus module for one of these. I have a few used ones in the might be useful one day box. (recovered from meters that were converted to wireless M-Bus for automated readout)