29 April, 2017

Building a photovoltaic solar panel using transparent polycarbonate (Updated)

Update: Before you continue reading, please let me discourage you to use polycarbonate, (as I explain at the end of the post): You will be loosing money for the only reason that the cells and the polycarbonate doesn't have same expansion coefficient and lets the water go through it (very slowly), and all the efforts to avoid this disadvantages will fail miserably.

In this post we will see how to build a photoelectric panel DIY the most economical way, yet it is safe and durable (has to endure 25 years). As we shall see, the difficulty of manufacturing is very high, so I recommend it only for the handyman ;). In addition the process is long, but very satisfying if you like the "do it yourself" and are fascinated photovoltaic panels.
I have seen many examples in Internet short - lived home panels , some prepared with wooden frame , I doubt that last more than ten years, or in sealed with silicone tight box (so that moisture comes but then condenses inside unable to leave quickly, corroding cells), whereby the potential savings to the panel in a home goes for the short duration of efficiently it.
As discussed in the previous post , my intention was to use polycarbonate, three times it economical than glass, plus much safer and lightweight whose only problem is that dilates 3 times more than glass, and has a light output somewhat lower than the glass (and falling further to whiten with the sun), but stays within a reasonable range during the first 30 years, which is what interests us.

To fasten the solar cells, I have sought more easily and economically; unused support or back cover, but linking them directly to the polycarbonate, and thus kill several birds with one stone :
  • Reduces material costs,
  • Quicken the panel,
  • Avoid possible accumulation of moisture and / or water, as the polycarbonate is not totally impermeable (no plastic is, unless a barrier metal), so it is desirable that no gaps where moist air can accumulate.
  • It allows some light to pass between the cells, so that the bottom remains partially illuminated.
  • Cells give one the more "fresh" are higher performance; per ° C above 25, panel lose 0.5% efficiency. If we let the rear "air" only with a protective coating (paint, epoxy or silicone), will be best refrigerar├ín, last longer and give more electricity.

19 April, 2017

Maintenance of the DIY solar thermal collector

Getter and repaired
Hello dear readers, I do not know in your area, but here in northern Spain we have had a February 2017 very very windy, with gusts over 100 km / h  (some kind of cyclogenesis ), so strong that it removed literally one of the panels of cellular polycarbonate, and after the noise we heard, we have found, pushed by the wind literally against a tree!

So light it is (1 cm wide and 1 mm wall), who knows where we have found it if the tree was not in the middle of his path. Even it had a brown mark, a sign that before it arrived there, it hit the tiles of the house, partially breaking it.

But this would not have happened if the panels had been properly anchored, and better protected from the wind. On the one hand, the wood of extreme suffering the ravages of rain, rotting it, it should put more sheltered. And secondly, the screws that secured panels only the timber were fastened, when should having crossed and fastened to the rigid metal under it much safer.

10 March, 2017

Cleaning and drying a smartphone that has fallen into water: Eg. the NEXUS 5X

To repair wet electronic boards , like a mobile that has entered him water, as this Nexus 5X that, despite rapid action he took water by charging connector, speakers and hole cards, it is best use pure alcohol or distilled water and an ultrasound machine , in addition to rub with a soft brush on the visible parts (and still no full guarantees, as if you were running shorts could damage a chip).
If you do not want to complicate , and you have 30 or 50 € which typically charge for repairing these problems, better take it to a repair center phones with good professionals, you will leave no trace of water or debris and running (but do not light after the accident), or try the Waterrevive liquid (which works very well if turned off immediately).
But if the water has not reached penetrate into the metal lids of the base plate (where sensitive to interference electronics is hidden), we can obtain very good results without ultrasound machine with brush and distilled water or alcohol (alcohol It has the advantage that evaporates easily later).
Waterrevive : A couple of young Spaniards have developed a liquid that promises that your phone back up and running in 98% of cases, they say. This liquid (possibly alcohol, distilled water or other solvent of mineral salts) introduced displaces water (containing mineral salts) preventing depositing causing short circuiting. Using this system has good result if we turned off / disconnected the battery quickly, before the lime and salt is deposited. If that system will not work, you can try these indications (100% of cases so far) .

09 March, 2017

Adding hot bed BQ Hephestos 3D Printer: Compiling and installing new firmware

If we want to print in ABS, heated table need

There are instructions on how to do this on the official website of Spain BQ, but are outdated and only explain how to do it in version 1.4.2 , which differs substantially from the latest firmware more refined versions , such as 2.3.1 or 2.4.0 ( do not not try it with 2.4.0, it gives compilation error at the very beginning).

Well, in short, I will show how to compile the firmware to serve you for these and subsequent versions , with optional hot bed activated and working properly. But first, I show how I've ridden (and there tutos on youtube so I save this part - The guy in this video , although physical and clothing clavadito me, not me lol).
A clause ... is a company of the stature of BQ should have precompiled firmwares with different options , and let the user choose (even versions with height sensors for self - calibration table), it is outrageous that a user who does not have know anything about compilers, have to eat the head ... even though deep down that is when you ride a printer that whole piece yourself ... but it is a trifle compile and save many headaches (there are several threads forums questions about this topic).
Before anything else, apart from the table, cables and thermistor, to feed the table need a power supply of at least 12V 8A ( best of 11 or more); the more heat amps before the table and more easily keep you warm. The most economical and reliable is to use an old power source ATW at least 300W, by looking at the indicating amperes for connection + 12V, are durable and well refrigerated fan:

08 March, 2017

Repairing and updating a Lacie NAS (Fvdw version at Plugout.net)

If you have a Lacie NAS with a broken hard drive, it is very difficult to recover the Lacie firmware/partitions, but we can replace the HDD and install the Fvdw firmware version with this tutorial and improve its possibilities by the way.

Previously I explained several improvements with hard drives (NAS) I drive, Lacie brand with Linux firmware.
These small file servers have as main advantage that allows us to have servers of various types, in addition to files with very low power consumption (less than 10W in general).
The fact is that there is an alternative firmware developed improved from the LaCie sources that have compiled Plugout.net guys that we can install in our NAS, which greatly improved the performance of our network disks , adding possibilities as possible choose media server (ideal for home), NFS, VPN, etc servers and download torrent files, among others. And it also serves to revive the NAS if the hard disk fails, and see, step by step, the installation process.
  • Faster , it is having been optimized with the latest software versions, up to 40% more agile list of directories and copy files.
  • More reliable, uses file systems safer.
  • More complete , with all the features expected from a small server.

13 January, 2017

Improving the Ebike with Arduino to monitorize battery and add anti-theft alarm 2/2

As discussed in the previous post, my goals to put a microcontroller programmed with Arduino on electric bike they were:
  • With an RGB LED display the charge / status of the battery monitoring one of the (weaker if possible) cells, to avoid surprises of not having enough charge for the trip the next day, showing orange when needed recharging (between 20 and 40%).
  • With an accelerometer and a powerful piezoelectric speaker  (and a mosfet to activate) we can add an anti-theft alarm, easy disabled with a button hidden from view, which is very handy against foreign's friends.
  • And even (this slope time), add light automatic brake  using the accelerometer (which changes from low intensity to high intensity when the accelerometer receives a deceleration in the axis of the fly), to keep usage statistics (number of refills, airtime, or adding small OLED display to show instant consumption in Ah with  a Hall sensor  (such as Allegro ACS75x, etc), battery charging, etc.
So this Christmas I could get down to work, and start to test in a breadboard to get something functional:

12 January, 2017

Extending the range and power of the bike by adding two cells in the luggage carrier

Before this project, the battery of my bike consisted of 8 cells in series of 6 batteries LiFePo4 A123 in parallel each, and I realized that I could have some more top speed and range by adding two cells with the previously left over LiFePO4 A123 batteries, and changing the BMS for the one I found of 10S and 60A (much better than the previous 15Ah only):

BMS / Control LiFePo4 charging battery cells 10 and 60A  maximum.
I will not cease repeating that if ye ride yourselves a Lithium Ion battery, you must put always a BMS, as this is essential prottection for the battery, cutting the flow of current in both overload and over - discharge in any of the cells.
One important note: This only works if you use the SAME type and state of cells for the additional cells (or you will get an unballanced battery fast, or worse, damaged cells that can't cope with the current).

On the other hand, increasing only 6V maximum load, I can still use the configuration of the motor control for 24V (having automatic cut if they drop too low voltage with the BAC-281P ebike controller, we cut prematurely the current if we use 33V battery with a 36V configuration). 

Features of BMS 10S LifePo4 60A load balancing ref. BMS-10SQZ6060LF375 :

Important data:
  • 10 Cells LiFe 3.6V, 36V full.
  • Maximum peak current: 90A
  • Constant current approx. without sink: 30A
  • Standby power consumption: 0.1 mAh (100 microamperes / hour).
  • For the rolling is effective with only 70mAh per cell balancing, the load should be as slow as possible (depending on the difference of load cells), recommended < 500 mAh.
As  I noted, the 12 could fit on a damaged old hard drive enclosure aluminum made.