Is there any way to get my emonpi to measure power coming directly off my solar panels.
I have a small off grid setup which goes solar panels---charge controller---batteries---1000w inverter.
Obviously I can measure the power used by connecting a ct clip on after the inverter, but I would like to find out how much power is coming off the panels and feed the data to my emonpi.
Re: Emonpi to measure DC ???
You face exactly the same problems with isolation as are being discussed in a concurrent thread.
Re: Emonpi to measure DC ???
I've read different methods but I need to know exactly what hardware I need to get this to work. Assume i'm completely new to openenergymonitor stuff. I only have a EmonPi. I'm not shy about soldering something.
There is this thread http://openenergymonitor.org/emon/node/4022 - but doesn't go into much detail.
Also there is this http://openenergymonitor.org/emon/node/10775 - Would this work ??
Re: Emonpi to measure DC ???
I've also seen enough about DC monitoring that it might be best for openenergymonitor to address this concern. provide some kind of sensor node.
Re: Emonpi to measure DC ???
As I wrote above, you MUST safely isolate your instrumentation if there's the remotest chance that it will be connected to something else. Isolating the current sensor is fairly easy - you can use a Hall effect sensor. Isolating the voltage sensor is significantly harder. Probably the easiest way is to add an emonTx and use the radio channel for isolation. You can then make direct galvanic connections on the input side, but it also means that your power supply needs to be isolated to the highest voltage possible in your system (and that might be the full string voltage plus the peak mains voltage) - or you do as Ian did and power from the dc itself, and you cannot connect a computer for debugging. Otherwise, you have to do something like GIVmon but for dc. That is a serious challenge and could well be rather more than just "soldering something".
Re: Emonpi to measure DC ???
dominator99 here has found a transducer that looks hopeful.
If Glyn & Trystan think there's a demand for a DC monitoring node, I've no doubt they will consider it. But I think the demand is simply not there in a quantity sufficient to justify the initial outlay. If you want to make and sell one, and go through the regulatory procedures to get it approved so that you can sell it legally, you're free to do so.
Re: Emonpi to measure DC ???
I was just wondering because I know of 4 people other then myself that would probably order some open monitor stuff for their off grid setup, if it was just a bit easier. I'm just a computer tech / java programmer so my skills with building components is not quite what the rest of yours are, but I'll try. I just need to find myself a step by step guide.
Re: Emonpi to measure DC ???
Here is one solution http://openenergymonitor.org/emon/node/11185