The majority of smart plugs have shunts that don’t detect very low current draws so low power devices end up just reporting 0 A and 0 W.
I need to run an automation based on when a low power turntable motor is running which will draw maybe 3-4 W.
None of my current plugs can detect this but from research I believe some can.
Does anyone have a list of cheap plugs available in the UK that are confirmed working for low power draws?
I have a SP-EUC01 from Aqara, it is connected to my desktop PC and reports around 2W usage when it’s turned off. I have a ESP32 plugged into the PC that is powered by those 2 watts.
@fleskefjes Is there a UK version with the same sensor?
I don’t know about your local availability but I have several TP-Link Kasa KP125M that read down to at least 0.5 W. I even have an automation that reliably triggers when it hits 0.7 W and then again when it drops from 0.7 W to 0.5 W.
Tapo P110. Reads 3W fine. Cheap and works.
My Ikea Grillplats plug reports 0.3 W for my washing machine in stand-by. Matter/Thread/HA
Who are those majority ones?
LocalBytes plug, two versions…
Tasmota version has a resolution of 1 W and reads down to 1W.
Current resolution is 0.01A
HA version has a resolution of 1 W and reads down to 1W.
Current resolution is 0.001A
Sonoff S60ZBTPG has a resolution of 1W
Current resolution is 0.01A
Same question here. Looks like there are many that could also detect under 5W just fine, based on the responses so far - all within hours.
So which ones you have tried that couldn’t do under 5W…? Think it’s equally important to list which plugs would not work.
I have Athom which goes down to 3w. It rejects anything less than 3w because the number may not be entirely accurate at such low levels. Or the plug is consuming watt or two.
I have a few power plug energy monitors around the house and while they report low power consumptions like 1W I cannot say what the accuracy is.
Here is my TV while it is off:
So the inference is they have a resolution of about 0.1W.
I use cheap energy Athom monitor plugs that DO NOT have a relay. They sell these for various regions. Nice thing is that the ones I buy are ESPHome programmable.
My 3RSP02028BZ by Third Reality, Inc Gen2 and Gen3 report in 0.1 intervals. Lowest I’ve seen is 0.2w on our Fireplace when off.
Our Kasa Kp115 also does under a watt.
So those are 2 options you can use. Both are cheap
I think all of my esphome smart plugs can do this easily.
Some plugs also throttle the sending of values (specially z&-tech limits here). With esphome devices you can force values to be send every second or even every 0.1s. Depending on the load type it might be impossible with only 10 seconds interval (zigbee?) too catch low power devices at all (even if in theory your coil/shunt can read it) 
Discontinued.
https://www.shelly.com/products/shelly-plug-s-gen3-1
I have 10 random plugs of different makes in use in the house. I tested them all and all show my turntable at 0 W.
To investigate this further, you should list what “randoms” you have.
I for one, would want to know which those are exactly: make / model / link or even pics, etc…
It would help other users down the road tremendeously.
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