diff --git a/content/img/case-inside.jpg b/content/img/case-inside.jpg new file mode 100644 index 0000000..e3a1828 Binary files /dev/null and b/content/img/case-inside.jpg differ diff --git a/content/img/hammond-enclosure.jpg b/content/img/hammond-enclosure.jpg new file mode 100644 index 0000000..8fe008a Binary files /dev/null and b/content/img/hammond-enclosure.jpg differ diff --git a/content/img/hammond-inside.png b/content/img/hammond-inside.png new file mode 100644 index 0000000..e98f1d3 Binary files /dev/null and b/content/img/hammond-inside.png differ diff --git a/content/img/voltmeister-100.jpg b/content/img/voltmeister-100.jpg new file mode 100644 index 0000000..cf3c1ab Binary files /dev/null and b/content/img/voltmeister-100.jpg differ diff --git a/content/posts/2014-11-24-voltmeister-100-atx-bench-power-supply-part-1.md b/content/posts/2014-11-24-voltmeister-100-atx-bench-power-supply-part-1.md index b2b5d64..9d22f93 100644 --- a/content/posts/2014-11-24-voltmeister-100-atx-bench-power-supply-part-1.md +++ b/content/posts/2014-11-24-voltmeister-100-atx-bench-power-supply-part-1.md @@ -26,7 +26,7 @@ This is Part 1 of a two part write-up of how I designed and built my first bench power supply. * [Part 1 - Design, schematic and PCB](https://ariejan.net/2014/11/24/voltmeister-100-atx-bench-power-supply-part-1) - * Part 2 - Enclosure and finished build - _coming soon_ + * [Part 2 - Enclosure and finished build](https://ariejan.net/2014/11/26/voltmeister-100-atx-bench-power-supply-part-2) ## The ATX Power Supply diff --git a/content/posts/2014-11-26-voltmeister-100-atx-bench-power-supply-part-2.md b/content/posts/2014-11-26-voltmeister-100-atx-bench-power-supply-part-2.md new file mode 100644 index 0000000..0304b02 --- /dev/null +++ b/content/posts/2014-11-26-voltmeister-100-atx-bench-power-supply-part-2.md @@ -0,0 +1,104 @@ +--- +title: "VoltMeister 100: Bench Power Supply - Part 2" +created_at: 2014-11-26 +kind: article +tags: + - electronics + - voltmeister + - power supply +summary: | + In Part 1 of this series I discussed how an ATX power supply can be used + to create a poor man's bench power supply. In Part 2 I'll show you how + I managed to fit the ATX power supply, my control board and everything + else neatly into a single box. +--- +In [Part 1](https://ariejan.net/2014/11/24/voltmeister-100-atx-bench-power-supply-part-1/) of +this article I've discussed the design and PCB layout for my _VoltMeister 100_ project. +I've converted an ATX power supply to a safe-to-use bench power supply. Although not ideal +for anything serious, it's a great way to actually get started and complete a project. + +This is Part 2 of a two part write-up of how I designed and built my first bench +power supply. + + * [Part 1 - Design, schematic and PCB](https://ariejan.net/2014/11/24/voltmeister-100-atx-bench-power-supply-part-1) + * [Part 2 - Enclosure and finished build](https://ariejan.net/2014/11/26/voltmeister-100-atx-bench-power-supply-part-2) + +## The enclosure + +I think that in a professional design process there is some tension between the PCBs you design, the +components you use and the enclosure you need to all fit it in. I tried to be smart and opted to buy a +'universal enclosure' that would fit my ATX power supply and leave some room for a small PCB. + +Because of the dimensions of the ATX power supply (roughly 140x50x80mm), I needed something that would fit that. +Note that most dimenstions specified when shopping for enclosures are _outside_ dimensions. + +In the end I opted for a nice Hammond enclosure, large enough to fit my power supply snugly and not +too expensive. It even has nice aluminium front and back panels. For those wondering, it's +the [1598ESGY](http://octopart.com/1598esgy-hammond-46506) from Hammond. + +![](/img/hammond-enclosure.jpg "Hammond Universal Enclosure")] + +Another thing I learned is to take a detailed look at the specification drawings. + +![](/img/hammond-inside.png "Inside the enclosure")] + +Notice the two supports circled in red? Yeah, those are used to screw the top and bottom parts of +the enclosure together. And guess what, my ATX power supply does _not_ fit between those +two supports and is now protruding about 10mm from the back. Booh! + +This is really a problem. I don't want to have an ATX power supply hanging out of the back. + +At first I thought of just buying a larger case, but I would not be that easily defeated. + +Because I'm curious by nature, I opened up my ATX power supply to see what's inside and +remove some of the cables I would not need. + +The PCB for the ATX supply is pretty tightly packed, but I noticed that transformer on the side was +not mounted on the PCB. There was a nice cutout on the PCB to allow room for the transformer. + +Putting one and one together I decided to remove the ATX enclosure and see if I could fit +the PCB in my small Hammond case. The transformer could be moved just a bit so it would +not interfer with the support inside the case. + +This worked brilliantly. All I had to do was make cutouts for the powercord and 120/230V +selector. + +The only reason I did this is because there is a clear separation between the high +voltage parts of the supply and the control (for the fan, I presume). Because the +orientation was just right, it would also shield my own PCB nicely. + +## The build + +Here you can see the inside of my bench power supply. + +![](/img/case-inside.jpg "Inside the case") + +The bottom half is filled with the ATX PCB. You can see the ground wire floating around, +this has been connected properly tot he front and back panels. + +The transformer is leaving a bit of a gap and has been placed just on the other +side of the support. + +On the top you can see my PCB with the ATX connector attached to it and wires going +out to the LEDs, the power switch and the different output voltages. + +## The result + +And, this is the end result. Suffice it to say that my precision drilling skills need +some more love. But other than that, I'm quite happy with how it turned out. It's my +first project, after all. + +![](/img/voltmeister-100.jpg "VoltMeister 100 in all it's glory") + +## Conclusion + +Building an ATX-based bench power supply like this is nice. If you need +a stable and reliable power supply, you're probably better off buying a cheap +linear power supply online for like € 50. + +I did this project to learn something. And I did. I learned how to SMD solder components, +I learned what to look out for when selecting an enclosure for your project. I also learned +about ATX power supplies and how you don't want to mess with them. These units handle +pretty beefy currents. If you don't know what you're doing you could end up hurting yourself. + +What's next? The VoltMeister 200, of course!