Good point, Chuck. Yes, the bill of materials here is not expensive. We're seeing this frequently with Gadget Freaks. Inventors are taking a few household items mixed with some inexpensive components and coming up with interesting gadgets.
Just found NEC book, article 690 covers PV, it applies even if not backfed into the utility system. Also, 690.4 states 'only qualified persons will be allowed to perform the described work on pv systems'. 690.4(e) Wiring and connections. The equipment and systems in 690.4(A) through (D) and ALL ASSOCIATED WIRING AND OTHERCONNECTIONS shall be installed only by qualified persons.
Article 100: Qualified Person.A person who has the skill and knowledge related to the construction and operation of the electrical equipment and its installation.This person must have received safety trainingon the hazards involved with electrical systems.
As you know, PV works in 3 states:
1. open circuit where there is no current flow and voltage can reach 600v potential
2. short circuit where there is no voltage and currents flow without damaging the pv.
3. in a circuit, where the voltage and current are proportional to the applied load.
When a pv output is opened they act like a CT. where the interrupted current is being pushed by the pv, many times drawing an arc while the voltage rises to open circuit voltage. This can be fixed by a shunting device, but I didn't notice one in the circuit.
Like I said, it works as designed but if it causes a fire will the insurance company pay the claim? 12 volts will burn down a house just like 120v.
One question to you as a PE, would you ceritify this installation to the inspectors and insurance industry as 'safe' if you had to put your PE license on the line?
WhEEngineer - Not sure what the NEC or the local inspectors might have to say about the details, but from how I read the article, the solar panel setup just feeds some 12VDC auxiliary lighting. If he fed that into the house voltage it would provide a whole lot of light for about one second and then the LED's would be no more.
The wiring is not to NEC code and I hope this isn't being backfed into the house voltage, and I didn't notice an isolator for the solar panel and an inverter. This is a great idea and works but the execution leaves a lot to be desired. Don't let an inspector or insurance agent see this setup.
I agree, proent. The strength of this entry is the get-it-done spirit. There surely could have been more costly ways to accomplish it, but this designer was determined to make the garage sale items work, and he did it in impressive fashion.
Though the result is not that effective aganst being spent much effort, time, material cost especially the wiring is pretty wirings ! Anyway I admire the strong sense of make it done spirit, I am pretty admired and respected the idea.
agree with earlier post. If I could find a free or low cost solar panel, I would build this, or a similar system. Without that, I would 'reverse' the main power source with the backup mains power source and just run off of AC with a backup battery and no solar! This approach would meet all functional requirements except social acceptability.
Sounds like the real advantage to this system lies in the bill of materials. Buying the solar panel and regulator at a garage sale, the entire project must have cost almost nothing.
Watching the video, I was fearing for Mr. Grill's health-- he sounded decidedly winded. Also, this isn't so much a standalone gadget as it is an installation project. Nevertheless, I'd have to say he put together something worthy and interesting.
What a great idea, and kills the proverbial two birds with one stone. My question: the caption for the second photo says "The LED based light modules were modified to maintain their sealed weather proofing." What was done to modify them for this purpose?
Using almost 200 light-emitting diodes in the front and back of the new 2014 CTS, Cadillac designers are showing how LEDs can change the character of a vehicle.
We looked at a number of sources to determine this year's greenest cars, from KBB to automotive trade magazines to environmental organizations. These 14 cars emerged as being great at either stretching fuel or reducing carbon footprint.
From Dell / Intel® New Paradigms in Design Work Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013 3
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
A quick look into the merger of two powerhouse 3D printing OEMs and the new leader in rapid prototyping solutions, Stratasys. The industrial revolution is now led by 3D printing and engineers are given the opportunity to fully maximize their design capabilities, reduce their time-to-market and functionally test prototypes cheaper, faster and easier. Bruce Bradshaw, Director of Marketing in North America, will explore the large product offering and variety of materials that will help CAD designers articulate their product design with actual, physical prototypes. This broadcast will dive deep into technical information including application specific stories from real world customers and their experiences with 3D printing. 3D Printing is
To save this item to your list of favorite Design News content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.
Tweet This
1 
