Logging usage of an electrical device

[u/AloysiusShiplap]

I'm aware of devices like the Kill-A-Watt and many smart plugs, which will track energy usage of a device. I want to do something slightly different -- simply keep a record of when the device is drawing power. Specifically, I'd like to know when a sump pump is running, and for how long. I suppose I could measure how many amps it draws, and then infer hours from Kw/hrs. But I'd prefer a more direct measurement. It could be a plug-in device like a Kill-A-Watt, but it could also be hardwired into a circuit. HomeKit connectivity would be a bonus. Thanks in advance for any suggestions!

[u/megared17]

Im sure any modern "smartplug" that had power monitoring, that was compatible with your platform could do that.

[u/grumpy_subscription → u/megared17]

you're basically looking for runtime logging, not just total consumption, and that's a little less common in the basic plugs

if the pump runs on a standard outlet, a flashed sonoff s31 running tasmota can do exactly this, it'll log on/off state by wattage threshold and that data can be tossed into home assistant or influxdb with zero cloud nonsense

[u/megared17 → u/grumpy_subscription]

Yes, but you can see "running" or "not running" by logging its realtime use., ignoring the cumulative counter if you don't care about that.

If its pulling power it running. If its not pulling power its not running.

[u/binaryhellstorm]

Smart plug with energy monitoring and Home Assistant, can do exactly that.

[u/realdlc]

Beyond using Home Assistant and creating binary sensors based on power draw data (which others have mentioned) there is also a direct approach, using a current sensing relay. (Example below)

You run the hot wire through the sensor, and it has a dry contact output. When power is drawn, it closes the dry relay contact. Just wire that into the sensor of your choice that works with your home automation platform.

https://www.amazon.com/Miniature-Current-Normally-Monitoring-Detectable（M3050）/dp/B0BG7YGTR7

[u/Vegtam1297]

Smart plug with monitoring is the easy answer and it'll do what you're after. Only thing I'd check first is what the pump is already on. The one here is on its own GFCI circuit. I didn't love putting something that reboots itself for firmware between the pump and the wall, so I went with a clamp on the cord instead. Is yours on a dedicated circuit?

[u/cosmicrae]

Monitoring of current level would be essential for something like a range. Current/watts being consumed is going to vary depending on which burners and/or oven is active. But they all draw current thru the same 220v wall plug. I've seen some DIN rail elements that can monitor exact current flow, but not so much for HA.

[u/zmannz1984]

I use CTs and data loggers for my job a lot, which has led me to explore home options and cheaper systems that still do what i need. There are many iot solutions for this now. Figure out how you want to store and communicate and go from there. I get a lot of results on google by searching “homekit power monitor.”

Looks like they don’t directly support it but there are products that will work for you.

[u/mwkingSD]

I have some Eve plugs that log usage in I think 6 second increments and will show that to you in a graph. I have a Shelly plug that does similar graph but I don’t know much about its logging. Shelly is very compatible with Home Assistant; Eve is less so.

[u/du_da2801]

that's actually genius, i never thought about just setting up a simple current sensor to trigger a binary state when it detects flow