OpenEnergyMonitor Community

Electricity meters with HAN interface

In my area of Sweden, the electric utility Mälarenergi is replacing all electricity meters with new “smart” meters that have a so called HAN interface for the customer to access data. This interface is a form of M-Bus. Believe that the same standard is used in more parts of Sweden and in Norway (and perhaps also some other country). Would be interested to know if anyone has integrated such an interface with OpenEnergyMonitor? Or would anyone be interested to do so (for example on Raspberry Pi)?

Can anyone give advice how such an integration would best be done, so it could in the future perhaps be part of OpenEnergyMonitor (for example as an alternative to CTs etc on emonPi)? I believe hardware is already available to connect HAN via USB, but are there any guidelines how the software should be best be written in order to possibly merge it with the other software?

A smart meter HAN - Home Area Network uses the Zigbee smart home wireless networking standard, however it seems to use a different ‘profile’ to most other uses of Zigbee and this I believe prevents directly accessing it.

There are some dedicated devices that use the same ZigBee Smart Energy 2.0 profile and hence can in theory connect. (This may or may not be restricted by the energy and meter supplier.) An example is this one Product Page - EAGLE-200 - Automated Energy Management | Rainforest Automation

These connect to the HAN using Zigbee and then convert the data to a form that can be accessed over your home LAN. (RainForest have their own API for this.)

In fact this type of device has its own abbreviation which is CAD - Consumer Access Device. You may be familiar with some smart meter devices which provide associated device with an LCD display you can view in real time on your table, these are called IHD - In Home Display devices and also use the same HAN. In fact some IHD devices now also have CAD capabilities as well. See - Smarter energy - Green Energy Options : Green Energy Options

Issues to be aware of.

SMETS1 and SMETS2 are obviously different. Some IHD/CAD devices may only support SMETS1 others may support both.

I believe that whilst the most common radio frequency for Zigbee is 2.4GHz that some SMETS meters may use different frequencies e.g. 868MHz. This is because these alternate frequencies have a longer range and with meters often being hidden away in a cupboard or even outside the house the greater range can be vital. Obviously you need to be compatible in this respect as well.

Thank you for your reply John. As I understand, ZigBee wireless is used for this purpose in the UK. In my area it is instead a form of M-Bus using RJ45, which can be used also to supply power to a slave. Below are some links regarding open-source solutions for the HAN interface used in Norway, which I believe is similar to what I have in this part of Sweden:ør-det-selv-og-Pilotprosjekter-ver-1.16.pdf (in Norwegian)

GitHub - roarfred/AmsToMqttBridge: Minimalistic system to read AMS/HAN data from electrical meter (however, I was very sad to read on Facebook that the developer is dead)

Using the instructions in Norwegian on one of the links I provided before, I’m reading data from the meter on a Raspberry Pi. Now looking for ways how to integrate it with OpenEnergyMonitor, view data in Emoncms and if possible also communicate data locally to a PLC using Modbus TCP.

Hi Sven

How are you reading the meter on the Pi?
I have a similar set up. I get the data using MQTT so I have NodeRed on the pi subscribing and then posting to Emoncms using MQTT. It also enables me to format data before posting to Emoncms.

Hi Ian

The Pi presently runs the software, which you can read about in Norwegian on the first link I provided before. It gets the data from the meter through a USB interface, which I purchased on the web. As I understand, an alternative software written in Python is available on GitHub - Danielhiversen/AMSreader: AMS reader, which can use MQTT (but I have not tried that yet).

There is a related discussion in Norwegian on Lesing av HAN - The Easy Way (TM) - WIP - Strømsparing og strøm-overvåkning - Hjemmeautomasjon, which includes for example information about different attempts to use Python

As well as using MQTT to send the data to an emoncms system, another possibility is to post the data over HTTP using the Feed API. To see how to do that, go to the Feed List page of your emoncms system and near the top of the page towards the right hand side there is a link ‘Feed API Help’. Click on that for details and examples.