240 volt capable smart switch with integrated power measurement

I just ordered a few of these devices:

100-240 Volt AC 50/60 Hz up to 16 amp for $13 (temp deal, normal $18) plus tax plus shipping.

and a slightly heavier one:

100-240 Volt AC 50/60 Hz up to 25 amp for $31 (normally $35)

Would be nice if this somehow could work together with the Sense unit in order to measure 240 volt loads like pool pumps etc.

There’s some limited info on the Wiki:

I could not find any API in case you want to measure the power consumption from your own app or program. But at least they’ve release the schematics showing the HLW8012 chip (Datasheet in Chinese http://www.tlola.com/en/Industry_Knowledge/2015/0828/64.html ) is used to measure power consumption, and is connected to ESP8266 via SCL and PWM1 pins.

The price seems right, and perhaps someone with more technical knowledge might see the opportunity to connect it with the sense universe.

The wireless relay can be controlled using Ewelink app for Android or iOS. But beside manually turning on and off the device, or settings timer like with all other Sonoff devices, you can also check real-time, daily or monthly power usage.

There become more interesting if you flash on a new firmware like ESP Easy:


Some good info the similar Sonoff TH by Xose Pérez (a.k.a. Tinkerman) here:

I haven’t tried any of the Sonoff products, but I have seen Sonoff integrations for Energy show up in the Home Assistant community:

Once you have the energy in Home Assistant, you can probably feed it to Sense via Home Assistant SenseLink.

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I’m clearly missing something.

How is this connected in a 240v circuit with only 1 line in, 1 line out and 2 neutral connectors :man_shrugging:t3:

Like most things in life, everything is relative.

Connect L1 → L on the box
Connect L2 → N on the box
Same with outputs.
What is labeled Neutral does not have to be connected to the real neutral in your breaker box.

And the 3rd wire On the 240v circuit is connected to what on the sensor?

A 240 volt connection has only 2 wires (plus optional ground wire)
If your application has 3 wires, you are feeding 2 x 120 volt which can also provide 240 volt.

My AC unit needs 2 x 120 volt, requires neutral from the grid and this box could not be used for that.

Real 240 volt applications that i have that use only 2 wires ( and an optional ground wire) where this box can be used:
-Hybrid water heater
-EV charger
-Electric clothes dryer

A pure 240V “balanced” device has no neutral wire as @dannyterhaar has a asserted. The problem is that many devices use balanced 240V for the main component (compressor motor, heating element), but also need 120V for other components (fan, controller board), which drives the need for the neutral wire.

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Which is really unnecessary nowadays.
Most switching power supplies have a range of input from 90-250VAC.
Since “other countries” have a standard of 230-240 volt from the beginning, you would think that everything would be designed for a more global market.
But my central AC happens to be one of those who rely on the split phase setup unfortunately.