LED strip integrated in Domotica system

Now that the new floor is nearly finished, i can start working on some Home Automation related subjects again; the first was using LED strips in the kitchen.

LED strips

LED strips

In total 4 segments of LED strip are used; 2 near the floor at the plinths of the lower kitchen cabinets, 1 at the counter top and 1 on top of the upper kitchen cabinets.

Today i finished controlling all these LED strips individually.

I don’t have Ethernet in the kitchen, so i used the ZigBee approach (again :-)). I mounted a XBee on a Sparkfun XBee RS232 board and connected it to the Chromoflex RS232 RX input:

XBee and Chromoflex in a box

XBee and Chromoflex in a box

The XBee RS232 board is powered by the adapter that also powers the Chromoflex, so all i needed was a wall outlet for the Chromoflex adapter and the Chromoflex was “connected”.

Now it was time to add control functions to my Touchscreen application, running on my Asus TOP in the livingroom. I added a “LED” button on the floorplan, in the middle of the kitchen:

LED button on the floorplan

LED button on the floorplan

And i found a very cool Trackbar Control and created a new pop-up form with it, that appears when you push the “LED” button:

LED Trackbar

LED Trackbar

With this form i can control each LED segment individually. To minimize traffic, i used the same approach as i did earlier with controlling my thermostat; a timer event fires when the Trackbar value hasn’t changed for 1.5 seconds and sends the new value to my Domotica System by XMLRPC:

VB.Net code

That’s all there is to it. My Domotica system takes care of the rest e.g. building the Chromoflex packet based on the USP3 protocol, wrapping it in a XBee Transmit Request packet and sending it to the ZigBee coordinator. Home Automation is sooo cool 🙂

Wireless LED strip control

Well, this post could just as well be called Wireless Chromoflex controller, or Zigbee LED Strip controller, or … 🙂

What i’m actually trying to accomplish is placing 14 meters of LED strip, split into 5 separately controllable parts in my house, without the need of additional wiring (i hate that!).  Just plug it into the mains and start using it… that’s the goal.

Yesterday the last goods i was waiting for arrived, so tonight it was time to make some sort of ‘proof of concept’; would i be able to control a Chromoflex by using Zigbee as transport medium instead of wires? Of course! Why wouldn’t it? But it’s always nice to actually see it working with your own eyes; and tonight i did.

Wireless Chromoflex

Wireless Chromoflex

In terms of programming, enabling my Home Automation system to be able to control an interface like the Chromoflex by using Zigbee, needed some additional coding. Normally an interface is addressed directly over TCP/IP or RS232, but this time i could not transmit the Chromoflex packet directly; it had to be encapsulated in a Zigbee Transmit Request frame. A feature that will be very useful in the future i guess.

To be continued…

Predictable LED troubles

In november 2008 i replaced 2 conventional fluorescent tubes by a LED version. Thinking they would last a long, long time was very, very wrong… In october 2009, not even a year after i started using them, the first tube started acting strange; one of the three rows of a total of 342 LEDs wasn’t burning anymore. Next day, the second row of 114 LED’s stopped burning. Guess what happened the day after that… a rough calculation tells me this tube has done its job for 360 x 5 = 1800 hours. Multiplying by 10 doesn’t even come close to what is advertised!

So i called the supplier for replacement tubes.

LED tube

LED tube, "version 2"

He promised me he would send me 2 new tubes, although he warned me in advance that it could take some time.. OK, i wasn’t in a hurry for replacement cause one tube was still working. But in the 2nd week of January i called again  to ask why it took so long for my LED tubes to arrive? The result was a very interesting conversation and i was given a bit of insight on how the LED market is working nowadays.

For example, i was told that the supplier had experienced a huge amount of failing LED light products being returned, especially during the hot summer of 2009. Bad design led to massive overheating of LED tubes and other LED products, causing lots and lots of  malfunctions..

Another thing the supplier told me, is that they had stopped selling most of the brands and had now limited their product range to only the high end segment; only those (with an equally high price tag) products could possibly live up to the life expectations that are so strongly advertised. Between the lines, you could read that his business had been seriously threatened by all the problems they faced with LED products in 2009. Quite a story for a normal ‘consumer’ like me who likes to try out new products, technologies and gather experiences with those products.

In my opinion, LED is hugely overrated in specifications, lifetime expectation and savings. I’ve bought at least 10 LED bulbs in the past year of which 3 stopped working in their first days. That’s 25-30%! within a week.  Needless to say i have very big doubts about the quality of the current LED technology.

And what will happen when my newly placed LED tubes stop working again in, say, 6 years? Will those tubes be replaced again, at no charge? Guess not.

No, for me LED is a nice product for the manufacturers, who don’t fully control the process of producing a good LED product yet but don’t mind making big money with it already, letting the customers pay 80 Euro for a single LED tube and delivering garbage.

And for politicians, who are encouraging the use of LED to show off how ‘green’ they are, while believing the LED producers on their blue eyes regarding to the quality of LED products. I wonder how much of them are actually using LED products themselves.

Me? I’ve learned my lesson and will not buy any LED product until my box of spare energy saving lamps is completely empty.

Replacing Fluorescent (TL) tubes with LED version

While doing all kinds of things to reduce power usage in our house (very good to combine with Domotica), i realised it was time to do something about those fluorescent tubes in my office.
There are 2 lighting fittings above my head, each one of them having 2 (120 cm) fluorescent light tubes of 36W. That’s quite a lot of light, but also Watt.
First thing i did was reduce the amount of tubes to 2. This still gave me enough light; but still i wasn’t satisfied and was looking for a way to reduce power usage further.
So i started looking for a way to replace these TL tubes with a LED version. After searching some websites that have lots of information about LED lights (like www.olino.org), i found these tubes.

Power consumption of these tubes is 15W, and they can operate without a ballast. If you’ve ever felt how hot a ballast can become, you’ll understand what waste of energy this is.

I decided to buy 2 of these tubes and yesterday they arrived:

Because i have to modify the fittings a bit (removing the ballast and rearrange the wiring inside), i have to wait untill next weekend before i can start replacing the tubes with their LED version since that’s the first time i’ll be home during daytime…

I hope that replacing the TL tubes with LED tubes will also reduce the noise i am experiencing from the TL tubes. That would be a nice advantage; this will save me a few X10 noise filters. And i’ll get rid of the sometimes very annoying time the TL tubes need to start giving light.

We’ll see what happens.