Archived Forum

As far as I am aware, nobody has published anything like that here. Much work has been done, and is still ongoing, on "disaggregation" (recognising a particular load from it's signature) and a search for that should turn up relevant threads.

If your CC setup is still working, you could connect the display's serial port to the Pi and push the data to emonCMS.

Now that's an idea, I hadn't considered that. I am using the serial connection to publish to the CC website right now but i know how to collect the data from the CC. I might need some help getting it interfaced into the emonCMS but seeing as i plan to run my own CMS on my server that has the CC sitting on top of it this might be quite easy. 

Thanks for the suggestion Aideen.

Thanks Robert,

Will have a look around now and see what I can find.

I haven't started reading yet so this might be a question that gets answered elsewhere but is there anything in the OEM range that can read the power draw through it that doesn't rely on a clamp?

Thanks Again

You mean a split-core current transformer? (When people write "clamp", I think busbar clamp.)  The shop kits use c.t's exclusively, for safety reasons. If you can easily and legally disconnect cables, there's no reason to use a split-core c.t. and you are likely to get more consistent and more accurate results with a ring-core one.

At various times people have suggested Hall effect devices, but these tend to be expensive by the time you've added power supplies and conditioning amplifiers. Any direct galvanic connection to the public electricity supply (e.g. a current shunt) means the whole equipment is considered "live" at all times and raises serious safety implications, usually meaning earthed metal enclosures, or double-insulated construction and an optically isolated interface for programming etc.

Must remember to be more specific in my questions :)

I mention clamp as in the C.Ts you mention as they clamp round the cable and are never very accurate compared to passing the supply directly through something that can measure it.

I am more than happy tinkering with the mains, am use to working on HV but in this case I was referring to something that would talk to the OEM setup that could be put in a box that measured the current being drawn from the mains ala the IAMs from Current Cost that I linked earlier.

There are lots of those type of inline enclosures out there from the ones that are remote controlled with on and off to the plug in energy / power meters built into them.

Something like this:

EBAY UK Domain /itm/Brand-NEW-Remote-Control-Mains-Socket-Adaptor-Set-5-Included-Remote-/380799510070?pt=UK_Gadgets&hash=item58a96b6636

or

EBAY UK Domain /itm/Power-Monitor-Monitoring-Energy-Socket-Ammeter-Analyzer-LCD-Watt-Voltage-Amps-/390704449455?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item5af7ccc7af

I was thinking these would be a good starting point and all i need then is something that works with the emonCMS system that can read the current draw. The units above are cheap enough to open up and change the guts. I am just a bit stuck on how to read the current and them transmit it.

Aha! You might like Node-RED (nice IoT software plumbing) and especially the very timely tutorials put

together by Dom Bramley which can be found at:

https://www.ibm.com/developerworks/community/blogs/B-Fool/?lang=en

Also try Googling for Node-RED and Currentcost or Node-RED and Wemo .... you'll get the picture :-)

Another interesting link is: https://blog.codecentric.de/en/2013/03/home-automation-with-angularjs-an...

Some of the power outlet switches they list are available at Maplin

Also interesting, but rather more expensive is the Ubiquiti mFi kit. e.g. see

http://linitx.com/category/ubiquiti-mfi/1057 and http://blog.linitx.com/ubiquiti-mfi-mpower/

On the 'disaggregation' front, it's possible to upload Currentcost data to Bidgely and Plotwatt - both

in the US. Bidgely aren't actually disaggregating UK energy data yet, not sure about Plotwatt.

Welcome to this fun and engrossing world. Hope you've got lots of time :-)

Jack Kelly did a lot of work decoding the CC protocols and wrote code to read and log the output from CC and EDF IAM's with a Nanode See here     http://jack-kelly.com/taxonomy/term/121 

There is also info on Martin Harizanov's site about decoding the signals from some of these plug in devices.

Thanks for the heads up. Will take a look as it seems sensible to reuse kit i have.

I have just been looking into feeding my weather station data (a Maplin N96GY - one of the Fine Offset rebrands) into emoncms and I am pretty sure there were a few forum posts over at Jeelabs.net dealing with Current Cost meters.  The search engine there is not very good for some reason so you might have more luck Googling their forums.

The solution I am looking at is using a node (probably a Moteino (lowpowerlabs.com) with a RFM12B) listening for the weather station broadcasts and then repeating these in the JeeLabs / Openenergymoinitor format which my RPi can pick up.

It looks like a combination of a bit of soldering and then a dose of bolting together various bits of code and crossing fingers.

You might find some of these links useful:

http://jeelabs.net/projects/cafe/wiki/Receiving_OOKASK_with_a_modified_R... [using an RFM12B to look at OOK, it seems you can use an 868 to cover 433 transmissions as well]

http://jeelabs.net/projects/cafe/wiki/NRfMon_-_nano_Spectrum_Analyzer_wi... [finding out what signals are in your area]

http://jeelabs.net/projects/cafe/wiki/Decoding_the_Oregon_Scientific_V2_... [some general info on decoding that was useful background and worth a read]

http://jeelabs.net/boards/9/topics/2103 [If you are feeling very adventurous the housemon project looks very exciting but way beyond my skill set at the moment]

Gary

For N96GY weather stations, there's great information at: http://www.susa.net/wordpress/2012/08/raspberry-pi-reading-wh1081-weather-sensors-using-an-rfm01-and-rfm12b/

Also worth searching the RaspberryPi forums.

I did think about that approach as well but am not sure I can go that route as I already have a RFM12Pi on the GPIO headers for emoncms.  If I was to double up receivers then I suspect the RPi would start struggling.

The hope is that an arduino node/Jeelab approach will also allow my push the data straight into emoncms and save doubling up on databases and cross-feeding info on the RPi.  I am slowly getting somewhere with coding on the arduino and would rather not spread my resources too thin in trying to tackle python as well.

If it works I will try and do a write up.

Sorry, editing out double post.

But can't resist adding... An excuse to buy another Pi?

I am running a couple at the moment, one with emoncms and another serving a webpage for the weather station using PYWWS with the receiver plugged into that by USB. Both are working well (touch wood) but just waiting for the inevitable SD card problem.  The plan is to get the weather station pushing data into emoncms and then I can look at migrating at least one RPi over to the SD card/HDD set up for resilience.  I can see this taking a while!

I know the feeling :-)