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Kamstrup Omnipower meters in Sweden: Which configuration should you choose?

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Swedish grid companies have for some time rolled out Kamstrup Omnipower meters that follow the HAN-NVE standard, defined by the Norwegian "Norges Vassdrags- og Elektrisitetsvesen" (NVE). Those meters are supposed to be used with the HAN-NVE module, but we made the Pow-K that replaces this module.

Since starting that rollout, Sweden decided to go for the more modern "P1 companion" standard. Omnipower meters configured for this standard are supposed to use the HAN-P1 module.  The current design of the Pow-K (layout v1.5.1) can be used on meters configured as "P1", but need a small modification (a soldered strap that connects two pins on the connector). The next, upcoming layout will have this implemented on the board (v1.6.1 is expected to be in sale around early April -24).

If you already have a Pow-K v1.5.1 or earlier that you need to use on a P1-configured meter, contact us for information on how to solder in that strap.

If you want to buy the current Pow-K board (v1.5.1) and use it on a P1-configured meter, notify us when you place the order - and we'll make the strapping.

The different grid companies have different ways of handling this transition.

  • Some insist on doing a remote upgrade of your meter to P1, in which case you need a modified board (or wait for next generation).
  • Some will let you choose between HAN-NVE and P1 configuration when you activate the HAN port.

It can then be useful to understand that there is an advantage in selecting "P1" configuration:

The two standards will deliver two quite different payload formats. In this context, the "Payload" is the data package the meter sends to the HAN port every x seconds.

You can find full information on that in the "Omnipower HAN Interface Specification", but here is a short summary:

  • The HAN-NVE payloads sends accumulated energy (kWh) only once an hour, in a longer payload containing more data points. This payloads is sent a few seconds after whole hour, and if you want to forward it over MQTT to for instance Home Assistant, it will be time stamped in the "wrong hour", meaning that Home Assistant will indicate the hourly consumption one hour later than the actual measurement.
  • The P1-configured meters always send a full payload, containing accumulated energy - and by that there is no time shift issue in Home Assistant. The payload also gives some more information, see paragraph 5.3 of the document linked above. Some users appreciate having power per phase - which is not delivered in any HAN-NVE payloads.

So our recommendation, if you can choose, is to go for P1 configuration.

Note: Some grid companies will use the type of socket on the module to distinguish between HAN-NVE and P1:

  • RJ45 = HAN-NVE
  • RJ12 = P1

Leave a comment


  • Help in solder strap
    By: Gösta Carlstrand On 14-Feb-2024


    I have purchased a Pow-K v1.5.1 a now my grid company has changed from HAN-NVE to P1.
    Im glad to hear you have a solution to fix this by adding a solder strap, can you give me some more details on how to do this? I am not that familiar with electrical circuits nor soldering so if you are able to assist me with some pictures or video would be great.

    Thank you and take care!

    Yours Gösta

    Replied by: Egil Opsahl On 21-Feb-2024 Hi Gösta,
    Sorry for seeing our message a bit late.
    Please email us on - and we will guide you.