How do I read my power meter in a rented apartment?

Hardware
1

Hey everyone,

I currently live in a rented apartment and would like to read my electricity consumption on my apartment’s smart meter. For this I need some tips regarding hardware, software and implementation.
I am running Home Assistant in my apartment on a Raspberry Pi 4 and have set up Zigbee in addition to my WiFi.

The smart meter is an eHZ-P from the company EMH-Metering. (Please excuse, the link is in German). Currently the smart meter measures data only locally and there is no data connection to the metering point operator or anyone else. However, the meter has an optical data interface for customers to push data via SML protocol. There are different opto heads for this.
So a possible solution could be a Raspberry Pi with an opto head.

Now to my problems:

  1. The smart meter is located in the basement of the house where I live. My Wifi does not reach down there, but I have a Zigbee connection down there (I use a Zigbee socket in the basement to track the consumption of my washing machine). So to send the measurement data from the basement up to my apartment, I would either have to use Zigbee or resort to some other data communication (LoRa if necessary?).
  2. Since the meter is in the basement and thus in the “public” part of the building, I don’t have direct access to electricity there. I’m not familiar with fuse box wiring, unfortunately, so I can’t assess whether I can tap power there directly. My guess however is that I can’t, since I can’t find a power outlet there either. So unless I can tap into a direct power source, I would have to use a battery solution.

Do you guys possibly have any ideas on how I can solve these problems?

2

Is there a distribution switchboard in your apartment?

3

Yes there is.

4

Then the easiest thing to do would be to fit a Shelly EM in there.

5

Thanks for the hint, I will have a look at this.

6

If you are into DIY the cheaper PZEM004T works well with ESPHome.

1 Like
7

Yes I am very much into DIY. Will take a look at the PZEM004T too. Thanks tom!

8

I actually found another solution which comes close to my initial plan.

With this LoRaWAN sensor I could use the SML interface on my meter in the basement. I just need a LoRa-Gateway.

9

Less chance of someone messing with your sensor if it’s not in the basement though.

10

Can you let me know if and how you get it to work and how you integrated it to HA?

11

Will do. At the moment I unfortunately have other things to do, but once I get back to this project and get it to work I will post my solution on here.

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