Showing posts with label light fitting. Show all posts
Showing posts with label light fitting. Show all posts

Monday, 8 January 2024

Hardwood slim line LED panel light fitting with accent lights

I recently purchased a pair of low profile LED ceiling lights from a charity auction on Ebay.

It seemed like the kind of thing that I’d find a use for eventually, and it was for a good cause.

After buying I had a message from the seller to tell me that they only had one driver for the two panels – I went ahead with the purchase because at the end of the day I wasn’t expecting them to be new and pristine from a charity auction.

My curiosity was piqued when they arrived. I noticed another label sticking out from underneath the address label. I peeled it back, and revealed an Amazon delivery label to a different address.

Initially I figured perhaps it was an Amazon returned item – one of the drivers was missing, therefore the original purchaser returned it, and it was sold on to the charity as one of those wholesale return pallets that you see advertised.

I did also think that the wires on the mains side of the LED driver seemed a little bit thin. However I tested it with those panels and they actually seemed to work okay, so I didn’t think much more of it.

Losing faith

So, I started to put together a project plan to make a light fitting with them.

I wanted to add in a few extra accent lights but everything I had was 12v, and the light fittings driver was 18v. While I was mulling over options – adding in a separate transformer, the space and heat issues to work round, etc. I noticed a couple of other things.

The case of the driver seems to have fake screw heads stamped on them. Not in itself a problem, but kind of sketchy.

And the panels themselves are stamped with 18w, not 18v.

The output of the driver says 9-18v at 300ma.

W=V*A.

There’s no way that if those panels are 18w, the driver can provide enough power to them.

This made me rethink my theory on the background of these lights.

Having a look on Amazon I can see very similar products, with identical looking drivers – the only difference being that the outputs are rated differently.

My guess is that this set of lights came with incorrect drivers, and the original purchaser damaged one whilst trying it.

It’s only a theory and not enough to make a claim against, it ultimately is enough to destroy my faith in these lights and make me not want to use them as they are.

Rebuilding the electronics

I had built the design around the size of these panels, so I decided to rip out all of the electronics.

On doing so I realized that the panels were just flexible LED strip edge mounted to a diffuser.

I swapped out the LED strip that was there with some white 12v strip LEDs. I had to trim about a millimeter off the sides of the diffuser in order to account for the slightly larger LEDs.

In an initial test the LED light was quite patchy, so I took the diffuser from the second light and doubled up. This makes a notable difference.

To drive the strip I’m using a regular RGB LED control box.

Initially my choice of this was simply because it was available and had a small profile so would fit well in the fitting.

However this also gave me the idea I could run the accent lighting and the main light on different color channels, allowing them to be controlled separately. It would also allow me to dim the light.

The design

Because I don’t want to carve out my ceiling to flush fit the panel I planned to build a small mitred frame, with another frame mounted at forty five degrees behind it. The back frame would contain some accent lights, with the front frame housing the main light fitting.



the fitting needed to fit in with the of our lights in the room, so I disassembled the original fitting and spray painted it black.

For the wood frame I opted to use zebrano.

The frames are simple squares with 45 degree mitres, and a 2mm deep by 10mm wide rebate to fit the light fitting frame flush with the surface.

The back frame was turned at a 45 degree angle, and screwed to the front frame.

The back frame also had a pair of key hole plate mounted to the back, which will be used for connecting to the ceiling.

Accent Lighting

Rather than cut up the filters from the second light, I opted instead to use a stack of filters from an old PC monitor. It was simply a case of measuring out the triangles, cutting them and then gluing them in place with hot glue.

Each corner would have a single segment of white LED strip (3 LEDs per corner). These would be connected in series and then connected to the RGB LED control box, on a different color channel to the main light, allowing them to be used independently.

The rest of the electronics

The IR receiver from the control box sticks out behind the front frame, so it is not visible from ground level, but catches enough reflected light from the ceiling to function.

However, this didn't last long and soon found itself wrapped in black tape because what I didn't realise at the time was that the IR receiver worked on the same encoding as our TV remote and we soon bored of having the lights change as we scrolled through TV guide menus.

PSU

The power supply is provided by an AC-DC “wall-wart” – I had to be quite selective in which one I picked to fit within the frame. The one I opted for had a removable face plate which allowed me to remove the socket pins and wire directly into.

The end result

 



Thursday, 10 December 2020

Live-edge oak spotlight light fixture - part 2 - adding ambience

In my previous post, I built a hanging light fitting of live-edge oak and recessed GU10 spotlights.

There is actually more to the project.

Sometimes, spotlights can be a bit overpowering, and it's preferable to have some ambient, indirect light.

During construction, I had the idea of creating this light in a way that would allow use of the spotlights, an ambient light, or both.

To create the ambient light, I used LED strips on the reverse (upward-facing) side, to reflect light off the ceiling.

I cut some thin strips of oak with a 45-degree angle and mounted them in a rectangle on the back - angled side outward, to help direct the light. An RGB LED strip was mounted all around this.

Control

I initially thought of using the LED driver that tends to come standard with rolls of LED strip, but as the existing wiring leads to only one switch, without some rewiring through the ceilings/walls, it would be limited to either having both the spotlights and the ambient light on, or just the spotlights on without the ambient light - it would not be possible to have the ambient light on without the spotlights.

In order to combat this, and to lay groundwork for a potential future project, I included a solid-state relay and an Arduino. The arduino would drive TIP31 transistors to drive the 3 channels for the LEDs red, green and blue, and additionally control a solid state relay which would act as the switch for the spotlights.

The idea would then be that the light switch would remain on, more like a utility switch, and then all control of the light fitting would be handed over to the Arduino.

 

Power

 

The original wiring sketch.
it's just a rough sketch,
not a proper wiring diagram.
 
The LED strips take 12V, and the microcontroller takes 5V, so a PSU is needed to bring the power down to usable levels.

For this I used an old net-book power supply. This was wired into the back of the light fitting. Caution is needed to make sure that nothing too powerful is used, as typically a houses' lighting circuit breaker is tripped at a much lower current than the mains sockets.

 

Revised to include the additional components
This would normally be plugged into a wall socket, where it's plug would have a fuse. However in order to wire this into the lighting wiring, the plug would need to be removed - obviously this introduces a safety concern. To ensure that this would still be fused, I replaced the wall switch for the light to one that includes a fuse, ensuring that the light is behind the fuse.

 

Communication

To communicate with the Arduino, I used a cheap HC-05 bluetooth to serial adapter, the same as I've used in other projects like the Bluetooth Macro keyboard app.

The arduino receives 4 bytes, followed by newline characters. These correspond to 1 byte each for the red, green and blue channels in the LED strip, and the final byte is either a simple 0 or 1 to indicate if the spotlights should be on.

For now this is sent by pairing with my phone and using a bluetooth serial terminal app from the Google play store. I'll probably create a more custom app in future, but for proving the concept, this works just fine.

 

Saturday, 28 November 2020

Live-edge oak spotlight light fixture

The basic idea

The idea is that the fitting uses GU10 spotlight fittings like those typically recessed into ceilings.

However, instead of recessing them into the ceiling, they're recessed into a piece of live-edge wood, which is hung from the ceiling like a more traditional light fitting.

The woodwork

There's not much really in the way of woodwork in this project, just clean off bark and splintery bits from the live edge, preserving as much of the edge as possible.

Quite a bit of sanding was also needed to clear up the surfaces.

The end of the board I had was cleanly sawn which I thought detracted from the live edges, so I broke the corners down with a carving disc on an angle grinder.

Creating grooves for
the spotlights latches
Then measure the centre line. I started by taking the average width of the board and working from that, but there is some leeway - having both sides be live edge makes this near impossible to find a perfect centre line, but ultimately as long as it looks central to the naked eye.

The spotlight fittings are not designed to go through the thickness of the board - after all, they're intended for plasterboard ceilings. While it won't affect the functioning of the light, it means that the spring loaded clips that latch. To work around this, I used a forstner drill to thin around the edge of the spotlight holes where the latch would sit - This is easier to do before the main spotlight hole is cut out, to stop the forstner bit from slipping.

Then I cut out the holes for the spotlights by drilling a pilot hole and widening with a jigsaw.

Test fit of one of the light surrounds

Wiring the spotlights

The three spotlights are wired in parallel, split across 2 junction boxes. Having them in parallel means that if one bulb was to fail, the others could continue to function.

 

To make installing the light easier, the lead that connects from the ceiling to the wood itself included a 'kettle plug' style plug and socket, simply so that the wiring could be done on the workbench, and just plugged in at the time of installation.

 

Mounting

The ceiling roses were purchased, and have simple hooks on them for hanging the chain.

Eyelet screws were attached in the back of the wood at each corner, from which the chain was attached.

Enough leeway was given on the chains so that adjustment could be made to ensure that the light hangs flat.