Reading my electric meter with RTLSDR

https://pdx.su/blog/2024-03-17-reading-my-electric-meter-with-rtlsdr/

by squidhunter • 2 years ago

31 11 2 years ago

My old house had a meter that could be read by rtlamr but the new one has a newer meter that sends encrypted data back over some proprietary mesh network, and no longer provides that data in cleartext.

I wish there was an open standard and one I could easily plug in to. Even just a flashing LED on the side of the meter would work for me.

heywire2• 2 years ago

I agree. Right around the time I figured out the format of the data from my Elster electric meter, they enabled encryption across the mesh network. Luckily the water meters remained in the clear, and our natural gas utility uses Itron, which are easily read with rtlamr (like OP describes)

I actually have an appointment this week to have our electric and water meters replaced, as our utilities are managed by the city and they’ve switched to a new provider. I think they’re putting in Itron, and I’m hopeful readings can be picked up by rtlamr.

ellisv• 2 years ago

Just want to note that Itron has several models of residential electrical meters and they have the different capabilities.

quickthrowman2• 2 years ago

You can add your own submeter after the utility meter, if you want to monitor your power usage. It’s more expensive than utilizing the utility meter, but sometimes you don’t have a choice.

Here’s a leviton kit with a 120/240v 200a meter and two CTs:

https://www.homedepot.com/p/Leviton-Series-1000-Single-Phase...

Equipped with both isolated pulse output and RS-485 serial port (modbus native) standard for easy interface with most AMR and BAS systems

ArchOversight4• 2 years ago

I believe the description is wrong. There is no RS-485 serial port on these devices, at least not what I can find in the manual/wiring diagrams. There's just the isolated pulse output.

RebeccaTheDev• 2 years ago

My utility also installed smart meters a few years ago - the Focus AXRe with Gridstream RF. It theoretically has Zigbee in it. It even has the Zigbee logo on it. It also uses some frequency hopping radio thing for reporting that I was never able to quite figure out.

But I DID discover that my utility, buried down in like 5 menus on some random screen of the account portal, offers a usage graph at 15 minute intervals. It's not real time - it seems to be delayed by 1-3 hours - but it is far better than getting a surprise bill. And while it used some weird SAP JSON interface, I could deduce what was what and could get the data out of it.

So I whipped up a script to basically scrape this "API" and shove the data into InfluxDB. I also added daily scrapes for the billing page and the rate page so I know when I was billed and how much the current rate is. This is because my utility bills at a lower rate for the first 1,400 kwh, and a higher rate for everything over that. I was not able to discern any pattern to when the bills were issued and the utility company was very unhelpful in this regard, just "sometime ever 27 to 35 days depending on holidays and weekends."

While I would really like realtime data directly off the meter, even being delayed a few hours is better than a random surprise $370 bill. I've written enough scrapers in my life to know it will probably break at some point, but it's been humming along nicely for the last few years.

upon_drumhead• 2 years ago

It likely uses ZigBee Smart Energy Public Profile, which while it uses ZigBee, doesn't work with generic ZigBee receivers.

https://www.home-assistant.io/docs/energy/electricity-grid/#...

And here's some details on the specs if you want to dig in and see if it matches what you are seeing

https://zigbeealliance.org/wp-content/uploads/2019/11/docs-0...

Reading my electric meter with RTLSDR

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