I have to get up while it is still dark and I do not want to wake my wife too much.
On the other hand I would like to be able to know what I'm wearing by other
means than the laughter of co-workers.
So I needed a LED strip in my closet.
Ikea sells a nice one, called "Komplement". I got one of those.
Then I discovered that my closet apparently is located in a "strictly no-power socket" zone.
So I needed a solution without wires.
This hack shows how to eliminate the need for a power socket for this LED strip, while
re-using the provided transformer(-case) as a battery compartment.
My need for the LED strip is each morning a few seconds, so a battery should last a
long time. YMMV.
as usual, do not complain to anybody if the hack fails. It's your own decision
and hence at your own risk that you choose to follow this instructable.
IMPORTANT : AT NO TIME SHOULD THIS LED STRIP BE CONNECTED TO A WALL
POWER OUTLET !
throw away the mains cable that might accompany the LED strip. You will not need
it during ro after this hack.
I encourage you to take the idea and change it to your situation/case/needs.
Let us know when you invent a solar version of this (didn't Ikea sell solar desk lamp ? hmmm..)
If you want to copy this literally you will need :
- Ikea Komplement LED strip
- sturdy pincers
- knife or cutting pincers
- phillips screwdriver
- soldering iron & solder
- bit of wire
- 9v rechargeable battery
- connector for 9v battery
- small switch
- some glue
let's get moving.
this hack wil not be pretty, but pretty effective.
I'm running two months now and I did not have to change the battery yet.
Step 1: Ripping Out the Guts
but you can show with a 9v battery that it works nicely on 9v as well. test it by connecting
the 9v battery directly to the cable hanging from the LED strip.
BUT BE SURE TO HAVE THE POLARITY RIGHT. If you do not know about "polarity",
do not do this test.
BTW : the LED strip has an on-board circuit (in the strip itself) that detects if the closet
doors are open or closed. This circuit consumes power whether the light is on or off.
You can see two little holes in the middle of the LED strip. if anything gets close to those
the light will switch off. You might want to snip off these two sensors, but you will need to
de-assemble the whole LED strip for that. I'll skip that in this instructable.
also, note a very tiny on/off/auto switch on the side of the LED strip. be sure it is not set to "off".
So, just connecting the battery permanently to te LED strip would drain it faster than
expected, because that door-sensing would go on 24/7. That is why we will simply
switch off the connection between battery and LED strip. You might get clever and
e.g. use a magnet on the door and a reed relay instead of a switch.
I just had a lot of switches handy...
First we are going to remove the electronics from the transformer case (the separate
square white box). Undo the 4 phillips screws and lift out the electronics and attached
plugs. The plugs are kept by some clamps, bend them back and there you go.
Sorry for the fuzzy picture of the transformer casing.
note that there is a black plug on the electronics board. This is where the LED strip
itself connects to. It is the only bit we are going to re-use. The rest is replaced by
a battery and an on/off switch.
The objective is now to break off a small bit of PCB with the black plug and two holes
for connecting wires (on the copper traces that connect to the black plug).see the pictures.
The challenge is to find a place to solder wires to this little black plug. we will re-use the
holes currently occupied by another component. Turn over the board so you see shiny
metal traces and locate two holes next to the black plug with traces leading towards the it.
These holes should be occupied by a blue capacitor (a blue cyindrical thingy next to the
black plug on the other side of the board). Wiggle this capacitor until it comes loose.
Check the photo's.
Next step is to isolate the black plug and the two holes from the rest of the board. This is
fancy talk for breaking stuff. YEAH !
With the pincers I was able to get a decent hold on the PCB and carefully break the PCB
in several places, working my way towards the black plug. Again, check the photo's.
If necessary remove small components (break or snap them off) to give the pincers
a good grip on the circuit board itself. Then twist the pincers so the breakline is alongside
the pincers. Be sure not to rip the copper traces off the board, at least not close
to the black plug.
Step 2: Throwing Molten Lead
we will connect one wire directly between battery(-connector) and the small bit of PCB. Be sure this wire is soldered in the hole that is closest to the thicker black part of the circle drawn on the PCB. see photo.
Then, the other wire from the battery(-connector) to a switch, and finally a third wire from the switch to the other hole in the PCB.
This is a standard circuit that can switch on and of power to the LED strip.
IMPORTANT : BE SURE THE BLACK WIRE OF THE BATTERY CONNECTOR CONNECTS AS SHOWN IN PHOTO to the PCB.
it is important because otherwise you would in effect connect the battery to the LED strip the wrong way round, which might damage the LED strip.
Step 3: And Bury the Remains
take the switch, the battery and the bit of PCB. mount the bit of PCB in it's original place.
Then (test-)fit the battery and the switch.
When you have decided how to put in the battery and the switch, there probably remain
three things to do
- snip off the bits of plastic that make the battery sit too high in the case (preventing you from closing the case all the way). I noticed some 9v batteries are slimmer than others, requiring more or less trimming. My battery is kept in place just by screwing the two halves of the case shut.
- mount the switch. As your switch might not be exactly like mine, you have to invent your own way of fxing it to the case.
- fix the black plug in place. I used a toothpick to press it into the case, you might want to glue it.
after this, shut the case with the phillips screws. decide where you want the case (and the switch !)
to be so you can easily reach it in pitch darkness. I mounted the case next to the LEDstrip, where it
is nearly out of sight.
you might want to give some thought about replacing batteries, as the case must be screwed open
for this. Just be sure the case can be removed if need be.
Now follow the normal installation procedures for the LED strip and the case provided by Ikea.
and presto ! Light where there was none. And less fashion surprises to boot.