Building a Workbench Light with the ON Semiconductor Lighting-1-GEVK KitFollow article
Making an enclosure for the ON Semiconductor Connected Lighting Platform power supply and control, and mounting the LEDs to use for workbench lighting.
On returning to the workshop after a period of working from home I decided it would be a good idea to tidy up my workbench. One thing that has never been really great, especially during these dark months, is the lighting.
As a start I added a diffuser to an attractive desk lamp that I had sitting on my bench for some time, but the light from which I always found a bit glaring. I used some laser cut frosted acrylic which made it a lot more easy on the eyes. Although that was OK, what I really needed was a good light for detailed electronics work, that would also be good for photographing projects in progress.
I had read the two blog posts that my colleague Andrew had written about the ON Semiconductor LED lighting kit and felt sure I could adapt that to my needs.
Making an enclosure
My first job was to build and enclosure to hold the power and control boards, and then a mount for the LEDs themselves. The ACDC Supply Board, as its name suggests, is mains powered and so I needed to devise a fully enclosed case for it. It connects directly to the LED Driver board, so my enclosure would need to accommodate that too.
As you can see, both of these boards are long and narrow and so that would dictate my enclosure’s form factor. As a prototype I laser cut an MDF base and fashioned a top for the enclosure from bent acrylic.
Once I was satisfied that I had the correct proportions I cut the base from a piece of 5mm Acrylic and mounted the boards on that.
The top would need to fully enclose the two boards, but as I may need access to the control board, I built it in two sections so that I could get at that without exposing the power board with its 240 VAC input.
The sections were made by laser cutting and folding 3mm clear acrylic sheet, with the initial design done in Inkscape and then exported to the laser cutter software. The red lines on the design image above are guides for where the acrylic is to be bent. You can also see the cut outs for a cable gland at each end to keep the cables secure, a power switch and fuse holder .
Finally I made 2 hooks — again from bent acrylic — so that I could hang the completed power and controller unit on the screen at the back of my workbench
Housing the LED strips
The lighting board itself features 2 strips of 16x LEDs — one a warm white and one a bright white — giving 7000 Lumen. The light was certainly going to be bright enough, but after my successful experiment on the lamp above, I decided that it would also benefit from a diffuser. Another thing to factor into the design was the heat generated by the LEDs, so I decided to incorporate a large heatsink into the lighting unit.
The metre long aluminium heatsink I acquired could be cut down to a suitable length and relatively easily drilled and tapped, to provide fixing points for the diffuser and the retaining surround for the LED strip.
I applied some silicon heatsink paste to the underside of the LED strip and then fixed it in place on the heatsink with a 5mm thick piece of laser cut acrylic.
Before completing the assembly I thought I had better test that everything was working OK. As the last time the lighting kit had been used it was paired with an Energy Harvesting Bluetooth Low Energy Switch and I wanted to control it with my ‘phone, the first thing I needed to do was update the firmware on the control board. This was easy to do following the instructions in section 5.2 for the kit’s Getting Started PDF guide, using the FOTA Mobile App that enables Firmware-Over-The-Air (FOTA) updates for the Connected Lighting Platform.
- Download the Connected Lighting Platform FOTA Firmware for either iPhone, Android
- Install the RSL10 FOTA app on my phone.
- Switch the target board into DFU Mode by quickly pressing the top button 3 times (this is where have access to the control board came in handy)
- Wait for the device to appear in the list of scanned devices in RSL10 FOTA app and click on it to go to the firmware update screen and in File section click SELECT FILE and select the lk_fl7760_peripheral_server_rtos_fota.fota file you down loaded in the first step (by default it will be in the Downloads folder on your ‘phone)
- Click on CONNECT to connect to control board. This will display the firmware version on the device and the FOTA image.
- Click the UPDATE button to start the DFU process and wait for the SUCCESS message to pop up.
When this was completed I was able to control the lights with the RSL10 Sense and Control mobile app on my phone.
Once I was satisfied everything was working as it should, I could complete assembling my light.
I had added a retainer for the cable and two pieces of diffuser at each end of the LED strip, and then fitted the u-shaped diffuser, again made from bent acrylic. I also added a shade made from white frosted opaque acrylic, to provide some added protection from direct glare. The lighting unit sits on a couple of arms made from 2020 aluminium extrusionthat are fixed to the rack of storage bins on my workbench.
I have ended up with what I think is a stylish looking lamp with a great lighting range — from a gentle warm light for everyday work, to an intense white for jobs where I really need to see what I’m doing, like the re-capping of a vintage Allen and Heath audio mixer which can be seen in the video above and is next up on my list of projects.