The emonPi will certainly do that. Actually, it presents the data as a web page on your LAN, so a PC or phone or tablet can be used to look at the numbers and the graphs.
Given enough input channels and access to the cables, we can monitor individual circuits going out of your distribution board. But automatically identifying and separating out individual appliances from their demand profile is a Holy Grail that, as far as I know, nobody has been able to achieve with anything better than a very moderate degree of reliability. We don’t measure in enough detail to be able to do that automatically. Your eye, and a knowledge of what you were doing and when, followed up by a bit of detective work, is likely to be just as effective if not better.
This is why I asked about what you needed now and what you thought you might need in the future. You can add an emonTx to the set-up at any time - that would give you the 2 channels in the emonPi plus 4 in each emonTx you add, but if you know exactly what you might need in total, that might not be the most economical route.
For now, given that all you want initially is the total consumption, an emonPi with 5 V d.c. power supply and emonCMS software on an SD card (all included), plus an a.c. adapter to measure the mains voltage (for best accuracy) and a current transformer to clip on the main incoming cable, is what you need. And access to your WiFi (or an Ethernet socket nearby and an Ethernet patch lead).
You’ll need two mains sockets close to your incoming supply where the emonPi will go - one for its power supply and one for the voltage monitor.
You do need access to a single-core incoming cable - probably next to your meter - on which to clip the current transformer.
My first thoughts are: First, what business equipment were you running, and can you estimate their consumption - it might not have been quite what you thought; and second, the most energy-hungry loads are usually heating. Those should show up readily in emonCMS when you’ve gathered enough data.
I’ll highlight this as it is easily overlooked as a requirement.
Can you send a photo of your meter location and / or the Distribution unit?
If the wiring inside the distribution unit allows and you are confident in doing so, it is sometimes possible to put one of the CT Clamps round the cable for one circuit so you can monitor just that circuit.
I will have to get a twin surface mount socket installed, I will get the front off the distribution board very soon and send on the internal image, bye the way as I in Southern Ireland can the software be configured to show Euros per Kw hr?
You might find you can get to the circuit wires as the Distribution Unit is quite large. However, you do need access to the mains feed from the meter as the CT clips round that.
It counts LED flashes from your meter. Two points: First, it’s totally accurate by definition (even though it might not be!); second, you’ll only know you’ve consumed a unit of energy after the event, when a pulse comes in. The c.t. measures power, and will give you the information at 5 second intervals (by default - it’s usually fast enough.
Your main use for the pulse counter would be to calibrate the c.t. accurately.
Note that if you have P.V, it won’t help much because it won’t count exported energy.
Hi Robert
Me again! my meter is on the outside wall so at least 5 mtrs from the distribution box by the time it has gone up the wall and through the loft (bungalow) would an extension cable male/female RJ45 be suitable or would that affect the signal?
Ian
Given that it sounds a deal of trouble to run the cable, I’d wonder hard why I need the pulse sensor. The emonPi should be accurate to within a few percent – from memory you have about an even chance that it’s within ½% and about 80% chance that it’s within 1%, even though the worst case error is appallingly huge.
I’ve never tested that sensor with an extension, but I don’t see why not, if it’s only 5 m or so.
But I’d keep it away from the main cables if that’s possible. We don’t know what’s inside the sensor so we don’t know how sensitive it might be to interference if you run the cable all the way right next to the main tails from the meter.
I wouldn’t bother with the pulse sensor. If you want to be able to measure the overall use and a circuit at the same time, the emonPi has 2 CT inputs so you can just use a second CT.
Neither would I - except to calibrate against. And from what Ian wrote initially, what he’s looking for is large relative use or sustained use that he can’t identify. And I think being one or two percent out won’t have a material effect on that.
I have an EmonPi with two CT as I have Solar, you can set the apps up to give any currency setup you want as the devisor will be the amount you pay for each Kwh. You can also set up an account on Emoncms.org as when you buy your EmonPi you will get enough “credits” for quite a few years usage and all your data is then up in the cloud (as well as on your own EmonPi This also means you can put the app on a smartphone and see the data from anywhere not just home. To get the ethernet connection to the distribution board I use a set of powerline adapters. As for adding a socket if you get on with USB charge ports on it this saves one socket
