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IoTaWatt Open Source WiFi Electric Power Monitor

iotawatt.com

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Re: IoTaWatt Open Source WiFi Electric Power Monitor

#31

Post by irq »

VectorLock wrote: post #23
daniellarusso wrote: post #15

Earlier quoted context omitted.

If this is possible, I know my breaker box has enough room, but is there any risk with all those cables with the 3.5mm end causing arcing? How do you route them out of the box? Should the wires criss-cross? Bundle them?

Leave everything in the breaker box and communicate out with wireless or optically isolated connectors.

You still have to plug in two wall wart style transformers (one is for reference voltage, the other is to power the box) into a real power outlet outside the box, and then get those wires inside the box. Or commit some electrical code sins and wire that inside the box too.

Re: IoTaWatt Open Source WiFi Electric Power Monitor

#32

Post by etcet »

joezydeco wrote: post #26

Just an FYI that your home may already have a grid-connected meter outside, and it may already have a wireless interface. For example, if you're a ComEd customer in the Chicago area, your smart meter is Zigbee-enabled and works with a handful of approved devices: https://www.comed.com/WaysToSave/ForYourHome/Pages/SmartMete... The information won't be as finely detailed since it's not sensing every circuit in the home…

You've just made me run outside to check my meter. What do you use to read it and are you happy with it?

Re: IoTaWatt Open Source WiFi Electric Power Monitor

#33

Post by irq »

1996 wrote: post #29

Is there anything simpler/cheaper that can go into a wall socket and be queried over bluetooth? (or join an existing wifi network)

All you can measure by plugging into a wall socket is (1) voltage; (2) power, but only for devices plugged into that outlet (by installing a meter like a kill-a-watt between the outlet and the device).

In order to determine power consumption for an entire circuit, or your entire house, you need to put a sensor around a wire in the breaker box. You can’t even do it in the walls because once power cabling leaves your breaker box, all the conductors for a given circuit are bundled, and if you put a current transformer around that bundle, it will show net zero power because it’s summing both halves of the AC wave.

You need to get a sensor around just the hot wire of the circuit, which is only accessible on its own inside the breaker box.

Re: IoTaWatt Open Source WiFi Electric Power Monitor

#34

Post by joezydeco »

linkalus wrote: post #27
joezydeco wrote: post #26

Just an FYI that your home may already have a grid-connected meter outside, and it may already have a wireless interface. For example, if you're a ComEd customer in the Chicago area, your smart meter is Zigbee-enabled and works with a handful of approved devices: https://www.comed.com/WaysToSave/ForYourHome/Pages/SmartMete... The information won't be as finely detailed since it's not sensing every circuit in the home…

Which device do you have that gives xml output?

Rainforest RAVEn USB. It looks like an FTDI-type serial port to a host. If you skip their application and just open the port it constantly sends data.

https://rainforestautomation.com/wp-content/uploads/2014/02/...

Might be discontinued now, but I think Rainforest's gateway product is a continuation.

Re: IoTaWatt Open Source WiFi Electric Power Monitor

#35

Post by danans »

mkoryak wrote: post #28

Dumb question: What do you do with this information? I can see it being useful for detecting anomalies, but for every day usage... I am not going to stop using my refrigerator to save power.

I used to work on the home energy monitoring space a decade ago. The most useful thing I ever heard of as a result of home electricity monitoring is that someone found a 100-W bulb that was always on.

If you have it connected to a major electricity consuming appliance, like a refrigerator, an electric dryer, or a furnace (whose fans use a ton of electricity), then in theory you can see any degradation in efficiency over time which may indicate that they need repairs. I doubt most people will do that.

For example, I'm pretty nerdy about energy use, and it took me 2 years to notice that the output of my house PV system had reduced 30% because of some trees that had grown taller.

Also, in the future, this sort of monitoring will likely be built into the appliances themselves.

There are also easier ways to achieve something like this, for example kill-a-watt meters.

Re: IoTaWatt Open Source WiFi Electric Power Monitor

#36

Post by joezydeco »

etcet wrote: post #32
joezydeco wrote: post #26

Just an FYI that your home may already have a grid-connected meter outside, and it may already have a wireless interface. For example, if you're a ComEd customer in the Chicago area, your smart meter is Zigbee-enabled and works with a handful of approved devices: https://www.comed.com/WaysToSave/ForYourHome/Pages/SmartMete... The information won't be as finely detailed since it's not sensing every circuit in the home…

You've just made me run outside to check my meter. What do you use to read it and are you happy with it?

Rainforest Automation device, see below.

Am I happy with it? Good question. I dropped RRTP last summer so I'm not as involved with it anymore. It doesn't really tell me much that I don't know, I suppose.

Re: IoTaWatt Open Source WiFi Electric Power Monitor

#37

Post by rootusrootus »

joezydeco wrote: post #26

Just an FYI that your home may already have a grid-connected meter outside, and it may already have a wireless interface. For example, if you're a ComEd customer in the Chicago area, your smart meter is Zigbee-enabled and works with a handful of approved devices: https://www.comed.com/WaysToSave/ForYourHome/Pages/SmartMete... The information won't be as finely detailed since it's not sensing every circuit in the home…

And even meters that don't have zigbee might be readable using an RTL-SDR. You do have to figure out which one is yours and which are your neighbors, though.

Re: IoTaWatt Open Source WiFi Electric Power Monitor

#38

Post by detaro »

joezydeco wrote: post #26

Just an FYI that your home may already have a grid-connected meter outside, and it may already have a wireless interface. For example, if you're a ComEd customer in the Chicago area, your smart meter is Zigbee-enabled and works with a handful of approved devices: https://www.comed.com/WaysToSave/ForYourHome/Pages/SmartMete... The information won't be as finely detailed since it's not sensing every circuit in the home…

And some power meters have IR-based interfaces. A "blink every X Wh of energy used" LED is quite common, but some also have bidirectional IR interfaces, recognizable by a metal circle with two lenses at the front (read heads are magnetic and simply set on the metal plate). (might be a European thing though)

Re: IoTaWatt Open Source WiFi Electric Power Monitor

#39

Post by ssl-3 »

joezydeco wrote: post #26

Just an FYI that your home may already have a grid-connected meter outside, and it may already have a wireless interface. For example, if you're a ComEd customer in the Chicago area, your smart meter is Zigbee-enabled and works with a handful of approved devices: https://www.comed.com/WaysToSave/ForYourHome/Pages/SmartMete... The information won't be as finely detailed since it's not sensing every circuit in the home…

AEP Ohio ended their program last year. But before that, they even went as far as sending out freebie Wifi-connected Zigbee bridges to interface the meter before the program went tits-up.

Now that there are zero applications for it, it's about as useful as a dumb meter.

Progress.

Re: IoTaWatt Open Source WiFi Electric Power Monitor

#40

Post by ssl-3 »

walrus01 wrote: post #21

I wonder about the choice of 3.5mm TRS stereo jack for the inputs. Ordinarily this would mean you need to buy prefabricated 3.5mm TRS cables and cut one end off to wire them up to the CT, because it's difficult or annoying to terminate your own 3.5mm TRS plug connector. Why not some other connector choice? Maybe RJ11, or one of the typical 'green' two conductor terminal blocks socket/plug combos with latches you can…

I haven't had tools to do 6P4C for over a decade and almost never used them anyway, but my soldering iron works great for TRS. I'm not displeased with this connector choice.

FYI, there are 3.5mm TRS adapters out there that have green screw terminals if that's your thing. They're very inexpensive.

But connecting my own current transformers isn't the intent here, I don't think. I think the intent is to have plug-and-play kits that are hard to screw up.

And the prices for their own CTs seem fine to me.

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