I still can't figure out the one thing I need to know..
I have a solar electric system, I want to monitor total home energy use, solar production, amount of electricity returned to grid...can I do that?
Also, does PC need to be on 24/7 for this or does monitor store data for download
thanks
Yes, you can do that. I'm doing that now with an ECM-1220. I have some charts being updated in real-time at a temporary web address.
http://www.bobshome.net/graph/energychart.php I don't specifically keep track of the amount returned to the grid since it's net metered, I'm mostly concerned with the daily and monthly totals but anytime green on the charts is above red, that's the amount being returned to the grid. So to kind of tie this in with some of the other posts. The ECM-1220's data is being read by the ECMServer program. Then I have another program that reads the data from ECMServer, processes it, and writes it to the various data files, one for each chart. Then PHP on the web page is used to read the files and generate the graphs. There are a couple of reasons this is fairly complicated right now.
1) ECMServer provides the same API as the ResidentServer program BrulTech has had available for some time. This API doesn't really allow for any processed data. It's mostly just the raw data from the ECM that gets output in a more user friendly manner. One of my goals for ECMServer is to expand and/or change the API to provide more processed data.
2) Both the ECM-1220 and ECM-1240 have what's called polarized counters on channels 1 & 2. Using the polarized counters, you measure the energy flow in one direction. The normal counters measure energy flow in both directions. If you are producing energy and feeding it back to the grid and you only looked at the the normal counter, you'd see the energy reading go from high -> 0 -> high as as the solar production goes from zero to max. So you need to know which way the energy is flowing and you have to look at both the normal and the polarized counters to get that. The ECM won't do any internal processing on that data.
The BrulTech monitors do have some internal memory that can hold the data collected. How long depends on the frequency it's logged. But come to think of it, I don't recall seeing any commands to extract the saved data. This is probably something Paul needs to answer.