Skye Sweeney's Build Log

Tonight I moved the current sensor from my test load (150W light bulb) to a real circuit in my main distribution box. That circuit is currently pulling nearly 500W at 121Vrms. It is logging data to a CSV file. It will be interesting to see what the plot looks like in the morning. It is not connected to Pachube.com right now. Perhaps by the end of the weekend. But with my taxes still to do, not sure how much time I will get.

I found the cause of my power switching from positive to negative. I would scope the current and voltage inputs one day and they would be in phase. The next day or even later that day they would be 180 out of phase. Well that is what you get when you unplug your voltage reference circuit and plug it back in later the other way. Without a three prong plug or one of those wide/narrow blade plugs, I can plug the voltage reference in two ways. One in phase and the other out. Time to add a switch to the reference so that I do not need to unplug it anymore!

Still have not figured out the difference between active and apparent power and energy and why one has the opposite sign of the other.

As I kind of suspected, Analog got back to me and informed me that the ADE7763 was a very mature product and that the reversal of IRMS and VRMS was never reported. Now unless NOBODY has ever tried to read these registers, than the problem must be mine. Continue reading →

I last left with a puzzle on my mind. The VRMS and IRMS registered seemed to be reversed. Changing the load did not vary the IRMS register by rather the VRMS. I figured I had screwed something up in the register definition enumeration or some sort of cut and paster error. Continue reading →

In my last port I alluded to the mysterious swapping of the voltage and current channel. When I read the Vrms and Irms channels under various loads, it is the voltage channel that changes significantly and not the current. I beat my head against the wall and found not reason for this issue.

I had considered that the SWAP bit was set in the mode register but repeated reads of the mode register indicate that the bit is not set. I even double checked by decoding the data on the SPI bus thinking perhaps I still and an interface issue.

I do believe that at one time it worked. I have notes that show changing current and not voltage. A lot has happened since that test. The SPI interface was changed to bit bang using direct port manipulation rather than using digitalReadWrite routines. I also implemented the zero crossing interrupt and the read of the RMS values inside the ISR.

I also have noticed that the phase of the voltage and current seems to swap on a daily basis. A few days ago, the phase was reversed and I swapped the direction of the CT around to fix. And yesterday I had to swap it again to get them back into phase. This seems to be very strange behavior and I wonder if it is related to the VI swap?

I also did some research and realized that the Arduino does have a hardware based SPI interface. This should be much faster than my bot bang approach and I will switch over shortly. If I can minimize the SPI time, I might just be able to sample waveform data at the slowest rate. This will go on the back burner till I solve the swap issue.

My ADE7763 is connected to an Arduino and I am now working on the interface code to aid in system testing. I sent several hours today with my mixed signal scope (2 channels of analog and 16 digital) debugging. What I have found is that on the whole the ADE is a pretty nice chip but it does seem to have a few rough edges. Continue reading →

Just started the first system testing of the ADE7763. What I mean is rather than just working on the SPI or other subsystems, I am using the chip as it would be in real life. I have the voltage and current channels of the ADE7763 connected to real sensors. Continue reading →

I have had an offline conversation with a reader about my endeavors with the ADE7763. Their application is similar to mine, but rather than monitoring at the breaker panel they wish to monitor (and control) at the plug level. I was asked to provide some pictures and schematics and so I do so here as well. Continue reading →