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.

  • Zwuzelmaus@feddit.orgEnglish
    1·
    21 days ago

    with MQTT client support out of the box

    I’m afraid you’d better give up that convenience of MQTT. It is a bit bulky when your highest prio is a speedy communication.

    • tofubl@discuss.tchncs.deOPEnglish
      1·
      21 days ago

      That’s not a hard requirement, but I thought it would be easier if the device pushes out a single message when there is significant change in current (as the Shellies do) instead of having to poll as fast as possible and hope for a timely response. My limited experience with these devices is that they are not the fastest or most reliable HTTP servers. I can poll a Shelly AZ’s state at a maximum of around 3 or 4 times per second, for example.

      A tight power_delta threshold and a millisecond timestamp in the MQTT message would probably solve my problem very nicely, but the Shelly I tested has no configurable threshold and only sends timestamps in minutes, which is of course unusable for me.