ADE7763 Part-3

Posted on January 30, 2012 by Skye Sweeney

Managed to get some time to play with the ADE7763 over the weekend. During testing of the SPI interface I found numerous problems with timing that I corrected. I am now fairly confident that the underlying digital interface to the chip is correct.

My next activity was to provide a zero volt signal to the V and I channels and insure that the IRMS and VRMS registers would read close to zero. They did not. I even enabled the DISCH1 and DISCH2 bits in the mode register to internally short the ADC inputs. But I still found that the values were not close to zero. I then noticed that If rather than shorting the inputs to ground if I connected them to a wiper on a 100K pot across Vcc that the IRMS and VRMS values would change. This counters my concept of a differential amplifier/DAC input. I sent in a request to Analog and hope to hear back soon.

Posted in Home Energy Monitor, Projects | 4 Comments

ADE7763 Part-2

Posted on January 27, 2012 by Skye Sweeney

Having recently gotten my DigiKey order I installed the crystal and its load caps on the breadboard circuit. Next I started to work on the communications to the ADE. I quickly learned that the Endian-nes of the ADE and and Arduino are opposite. I spent a fair chunk of time fixing the data transfer routines to account for this. Just before going to bed, I think I got the bulk of the issues fixed. I was able to write than read various values to a register. Next will be to test the heck out of the communication interface before trying to get the chip to measure RMS values. Perhaps by the end of the weekend. So far, I like this chip.

 

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ADE7763 for energy monitor

Posted on January 26, 2012 by Skye Sweeney

Stumbled across the Analog Devices ADE7763 IC. It is a chip dedicated to single phase energy monitoring. It has inputs for current and voltage sensors. The chip takes these values, computes the RMS values, takes the product, and integrates it over time to compute energy usage. The results (and many of the intermediates) are available over an SPI bus. Continue reading →

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Pachube and the furnace project

Posted on January 18, 2012 by Skye Sweeney

Just came across the website www.pachube.com. It allows a user to post data to their servers and then use their services to graph and otherwise manipulate the data. Think of it as the YouTube of dynamic data. Continue reading →

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Server crash (2.0)

Posted on January 13, 2012 by Skye Sweeney

Memory tests passed. Smartd tests on all drives pass. Connected oscilloscope to Power_Good signal that the power supply sends to the motherboard. There is an occasional glitch on the line. Perhaps the glitch gets a bit bigger at times causing the problem? Well I have left the scope connected and have not had another crash. I hate problems like this!

 

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Random crash of my fileserver

Posted on January 11, 2012 by Skye Sweeney

Over the last few weeks, I have noticed that my Linux based file server will randomly reboot. The first time I noticed it I did not give it much thought, but now it happens about once a day. Continue reading →

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Finding an old friend

Posted on January 9, 2012 by Skye Sweeney

Went to the dump over the weekend to drop off an old PC and hoped to find a better one to run in my home lab. As I approached the electronics area, something jutting out of a box caught my eye. What I found was an old Phillips oscilloscope. Just just any one, but the one I had dropped of at this same dump like 8 years before. It had the same dent in the chassis.

I hope the previous owner got as much use out of it as I did before I purchased my first LeCroy DSO. Hope the next owner (I hope there is a next owner) gets some use out of it as well. Trading at the dump is a great way to be green.

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A crazy few weeks

Posted on December 24, 2011 by Skye Sweeney

I have been unable to work on home projects for the last few weeks due to a huge push at work to meet a year end sales quota. We had numerous units unable to sell due to a communication error during environmental testing. Although the units would work perfectly for our customer, they failed our factory tests and had to be put aside. It was up to me to figure out the issue and enable their sale. After a significant number of experiments I was able to find the issue. In fact it was a “perfect storm” combination of numerous factors. Luckily a simple solution was found that prevented any system software updates.

So now that I have a week off from work for the holidays, I plan to get back into various projects. These including teaching my college son C++, fixing the RS-485 link to my furnace monitor, making a life casting of my son’s face, fixing bugs in my DVD robot software, working with a FIRST LEGO League team to improve their skills for next year, and sleeping in!

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NH State FLL Tournament

Posted on December 4, 2011 by Skye Sweeney

The New Hampshire FIRST LEGO League state championship was on December 3. I was the lead technical judge. To accelerate the judging process, we have 5 teams of two judges that each see 10 teams. At the end of the morning, the judge pairs must meet and merge are results into a master list. This is very hard to do because judging is subjective and each team can score as hard or as easy as they want. Numerical scores are useless. We must go over the top teams and discuss each one to properly merge the results. But at the end of the day, I think we did a great job and rewarded very deserving teams with gorgeous trophies made of LEGO.

If you are not aware of FIRST LEGO League, you should go check them out at http://www.firstlegoleague.org/

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Robolab for FLL

Posted on November 22, 2011 by Skye Sweeney

Last night I had the chance to work with a local FIRST LEGO League team using Robolab on their NXT robot. It was a very enjoyable experience especialy after the miserable day I had had at work. In the few hours I spent with them I was able to communicate significant engineering and programming concepts. Something I would never have been able to do in NXT-G. At the tournaments I had judged at in previous weeks, most of the teams were not using sensors. When asked it was because they “did not work”, “not as accuarate”, “too hard”, or any number of reasons. And when dealling with NXT-G language all very valid. But watching last night’s robot follow a line at nearly full bore just made my heart sing with joy. All teams should be required to use Robolab.

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