Hi all,

I’m looking for a reliable smart plug with current/energy monitoring that meets these requirements:

  • Ideally <1s time resolution (I need fast updates, not just averaged every few seconds.)
  • Wi‑Fi connectivity preferred, with MQTT client support out of the box (similar to how Shelly devices can publish to a local MQTT server when the load current changes. I’d rather not have to poll a device’s HTTP endpoint a few times per second.)
  • Provisioning/config: Bluetooth for setup would be a big bonus (I think the Shelly Plug S Gen3 can do this, too.)
  • Reliability/manufacturer: Needs to be from a well‑supported brand or at least something that’s proven stable and not a “cheap no‑name” option.

I’ve been testing a few devices already. Most average power consumption over longer periods, while e.g. newer Shelly devices come frustratingly close to being exactly what I need.

Does anything on the market provide sub‑second resolution for current measurement? Most consumer plugs I’ve tried either average readings or only publish once every few seconds, which isn’t quite enough for my use case (measuring transient behavior and categorising operating modes of certain appliances).

Has anyone come across a plug that ticks these boxes? Or maybe a hidden configuration with Shelly devices that I’ve missed?

Thanks a lot for any help!

Edit: What I’m actually looking for is a fast response time to significant changes in power consumption (by more than a set amount or a percentage), so a high sample rate within the plug. A constant delay until the message is sent out wouldn’t be a problem at all.

    • tofubl@discuss.tchncs.deOPEnglish
      2·
      5 days ago

      Thanks for the reply!

      I have no experience with esphome. This list has many of the “usual suspects” (Nous A1T which I have yet to test, Shelly Plug S) but how will this solve my problem?

      I see that there are a few like this one that come with esphome preinstalled (a requirement for me, I can’t use smart plugs I individually have to reflash.) In the device’s config file I see a variable sensor_update_interval: 10s. Is that what you mean?

      • Rogan Dawes@infosec.exchange
        01·
        5 days ago

        @tofubl yeah, the idea would be to flash your own firmware configured precisely how you want it to work. update_interval: would be one of the knobs you could tweak. Just be aware that whatever you are feeding the readings to may end up storing a huge amount of data, if it is updating at more than 1Hz! The esphome sensor filters might also allow you to get rapid updates when it’s changing significantly, and reduce the rate when you don’t need it.