Jul 9th, 2010 by Edmund Tse
After having the solar electricity system installed, I can monitor the energy output of the inverter using Pro Control. However, because the software runs on Windows, I’d have to have a PC turned on just for that purpose wasting quite a bit of energy. So, my goal is to use a low-power embedded Debian box (which is usually on) to do the monitoring. Instead of just writing an application to do the job, I’ve decided to write a library others can use to write their own custom logging software.
pv can be found at http://pv.codeplex.com/, and should work for you if you have a Carbon Management Solutions CMS-2000 or Schneider Electric SunEzy 600E (judging from a sample protocol exchange).
I’ll have to give full credit to the folks at http://www.solarfreaks.com/cms2000-inverter-rs232-serial-port-hack-cms-2000-rs232-t271.html who did the initial work on reverse engineering the communication protocols. Building on what has already been done on working out the protocol, and doing a bit of reverse engineering myself, the library supports sending arbitrary data frames for further exploring, as well as the known protocols.
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Tags: electricity, engineering, hack, Software, solar
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Jul 8th, 2010 by Edmund Tse
Not long ago, we took advantage of the various NSW government rebates plus the massive 66c/kWh EnergyAustralia feed-in tariff, and had solar panels installed on the roof of our house by Andrew Hanna Electrical. The specs of our system are as follows:
During the installation, they’ve kindly put a Cat5 cable through the house for the RS-232 serial connection from the PV inverter to the computer. The CMS-2000 is basically a re-badged Solar Energy Australia “Orion” grid feed inverter, which comes with monitoring software “Pro Control” to log data from the inverter. Armed with this software, we can now pull some interesting data to see how much energy we generate at various times throughout the day.
The only problem is, it doesn’t make sense to have a computer switched on 24×7 just to monitor the inverter box – it’d be a massive waste of energy. So the fun begins when I want to monitor the solar inverter from a low-power, embedded computer which is actually a QNAP TS-109 NAS running my favourite Debian linux. More on this in upcoming posts.
Tags: electricity, solar
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Jul 3rd, 2010 by Edmund Tse
After a bit of distraction, my study notes for ELEC5616 Computer and Network Security is finally finished and have been posted. As usual, it’s up my my Sydney Uni page.
Tags: engineering, lecture, security, USYD
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Jul 3rd, 2010 by Edmund Tse
The story behind this mini-project is, a friend of mine mentioned how he would SSH into his Mac at home and use “say” to send a short message to his parents, just like in a past XKCD webcomic:
Mac users, lucky you. You get a Terminal utility called “say” that converts text to speech. Windows doesn’t come with this tool, so I thought, it couldn’t be that difficult to make my own command line speech synth tool for Windows.
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Tags: application, Software, speech, synth, Windows
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Jun 28th, 2010 by Edmund Tse
Exams for semester 1 this year are finally over. The first set of notes to go up is for ELEC5509 Mobile Networks taught by Abbas Jamalipour. As usual, you’ll be able to find it at my Sydney Uni section of the blog.
I would have to say that this course is one of the least enjoyable and least rewarding courses I’ve done over the years, and would strongly advise those doing Telecommunications Engineering at USYD to not take this course.
Read on for a brief review of the course.
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Tags: lecture, mobile, network, USYD
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