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Monitoring Home Power Consumption for less than $25

blog.kroy.io

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Re: Monitoring Home Power Consumption for less than $25

#51

Post by pvitz »

inglor wrote: post #34

It's weird that he didn't give the ELK stack a chance. Kibana would be awesome at graphing this and data ingestion would also be very simple. Very useful for automatically generating graphs based on data. Would have automated the whole "writing PHP + jQuery + SQLITE3" part entirely - and consume the JSON directly and created visualizations based on that.

He mentions that it should be able to run on a Raspberry Pi. The choice seems pretty reasonable to me (or maybe I am missing the irony in your comment?)

Re: Monitoring Home Power Consumption for less than $25

#52

Post by kevin_thibedeau »

PoachedSausage wrote: post #35
lucaspiller wrote: post #11

Earlier quoted context omitted.

You can also buy clamp sensors that can be connected directly to a microcontroller (with an ADC - so not a Raspberry Pi without external hardware). http://www.homautomation.org/2013/09/17/current-monitoring-w...

The clamp only systems lack accuracy due to not measuring supply voltage. Commercial/open source energy meters based on chips like the ADE7953[0] have a resistive voltage divider to attenuate the supply voltage to suitable level for the chip but preserving the envelope for sampling. The problem is there is no galvanic isolation, so interfacing is harder. [0] http://www.analog.com/en/products/analog-to-digital-convert…

There are transformer isolated energy monitors like MAX78615. Much safer to work with.

Re: Monitoring Home Power Consumption for less than $25

#53

Post by emilburzo »

alkonaut wrote: post #45

Is it really required to actually read currents to achieve the power measurement? do meters in individual buildings not have interval-flashing LED's for power consumption in the US (I'm assuming the target market is the US)? A flashing LED is neat because you can then use a very simple-to-install adhesive photodiode to count the flashes and radio the results back to some reader (e.g. 1000 impulses per kWh). Doesn't r…

Would nobody bat an eye if you had an electronic device attached to the meter? (especially the guy that comes and does the meter reading)

Re: Monitoring Home Power Consumption for less than $25

#54

Post by Joe8Bit »

masklinn wrote: post #19

> Some research told me that the power company accomplishes this via a simple radio broadcast on the 900Mhz spectrum. Interesting. Around here (mainland Europe) they're currently installing "smart" meters which do this using CPL rather than radio. > And with one simple command, I was reading the power (and probably water) meters for my entire neighborhood That is a bit troubling from a physical security perspective,…

Interestingly, in the UK utilities are using GSM SIM cards in Smart Meters, and a mixture of SMS and data to monitor/send electricity usage.

Re: Monitoring Home Power Consumption for less than $25

#55

Post by masklinn »

SergeAx wrote: post #43
masklinn wrote: post #19

> Some research told me that the power company accomplishes this via a simple radio broadcast on the 900Mhz spectrum. Interesting. Around here (mainland Europe) they're currently installing "smart" meters which do this using CPL rather than radio. > And with one simple command, I was reading the power (and probably water) meters for my entire neighborhood That is a bit troubling from a physical security perspective,…

Did you mean PLC as in Power Line Communication?

Yeah, sorry.

Re: Monitoring Home Power Consumption for less than $25

#56

Post by icelancer »

ahoka wrote: post #36
icelancer wrote: post #17

>>I use PHP. There, I admitted it. Very happy to see stuff like this in blog posts. I use it all the time to stand up scripts like this. It makes me REALLY happy to see hacky code like: >>exec("/scripts/gocode/bin/rtlamr -msgtype={$type} --format=json --filterid={$unitid} --single=true",$output); I also do this all the time, even to control Windows processes on client/slave machines (generally killing and relaunching…

The problem that it takes a $type="; rm -rf /" to ruin your day.

No doubt, that's why stuff like this should be limited to internal tooling and private use only, not exposed to the Internet. When done that way, it's just infinitely more efficient to write trash code in PHP for one-off things, and there's literally nothing wrong with it when it has an audience of 1 - yourself.

Beyond that, yeah, you shouldn't do things like that. But there is no reason to stand up an entire test suite and development environment just to write some stuff to check power usage or internal sensors in your house.

(also that command would fail on the machines I run my crap code on, Win10 discardable VMs)

Re: Monitoring Home Power Consumption for less than $25

#57

Post by joelhaasnoot »

masklinn wrote: post #19

> Some research told me that the power company accomplishes this via a simple radio broadcast on the 900Mhz spectrum. Interesting. Around here (mainland Europe) they're currently installing "smart" meters which do this using CPL rather than radio. > And with one simple command, I was reading the power (and probably water) meters for my entire neighborhood That is a bit troubling from a physical security perspective,…

The only thing Dutch lawmakers got right is the requirements/specs for smart meters include a serial port ("P1") that can be read with a $10 USB cable.
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