# New Project: Modular Rack-Mount Power Supply System Introducing a new modular rack-mount power supply system for improved scalability and maintenance. Canonical: https://karlquinsland.com/announcing-modular-rack-mount-power-supply-system/ Published: 2026-09-19 Updated: 2026-09-19 Tags: project, MRPS --- # Announcing new new project: Modular Rack-Mount Power Supply System (mrps) Normally, when working on a project that I plan to release, I'll do all work in a dedicated private repo until the project reaches a certain level of maturity and stability. Once ready to release / share with the world, I'll make the repo public and write a blog post about it if it's deemed interesting enough. Usually, the blog post gets published here as a summary of the project with a healthy dose of personal/editorial commentary on the project, while the detailed technical documentation resides in the project repo. For the past several _years_, I've been working on a project that I hope to eventually release. As you'd expect, a project like that has a serious skill-tree that needs to be navigated and mastered over time. Today I'm announcing what is essentially a spin-off created from that larger project; a project that helps me develop some of those skills further and yields a useful bit of work that can stand on its own. After some deliberation, I've decided to do a few things differently for this project: - Not waiting until v1.0 is "ready" to start sharing progress. - Not doing an extensive write-up on the blog, but instead setting up a dedicated GitHub Pages site in the same repo as the core project and doing project specific updates there. This is a new approach; we'll see how it goes! ## So what is this project? A bit of a hint; It looks like this: ![screenshot of core Modular Rack-Mount Power Supply System components](https://karlquinsland.com/announcing-modular-rack-mount-power-supply-system/images/hardware-assemblies.webp) _CAD Render of core Modular Rack-Mount Power Supply System components_ For a considerably more detail, see the dedicated ["what/why" section on the project site](https://mrps.karlquinsland.com/#whatwhy). Concisely: - My compute needs have morphed over time and I now require a small, dedicated cluster of compute for some specific workloads. - Through a friend, I got a good deal on some second hand ["1L" computers](https://www.servethehome.com/perfect-project-tinyminimicro-pushing-a-1l-pc-as-a-server-concept-intel-hp-sabrent-crucial/) that are ideal for my dedicated cluster setup. - The small form-factor makes them ideal justification to build a ["mini rack"](https://mini-rack.jeffgeerling.com/). - In addition to the dedicated cluster, my primary compute clusters have outgrown [the power supply I built years ago](/home-lab-consolidated-psu/) for them. I'd like to build a much more capable power supply that can handle the increased demands of my primary compute clusters: - If the design is right, it should be adaptable to future needs like a workbench setup or other custom configurations. - It should not have any of the limitations of the previous design: - It must be easy to work on "live" while in operation; I shouldn't have to power down the entire system to do basic maintenance or upgrades. - Cable management should be straightforward and flexible. - The system should be modular, allowing easy replacement or upgrade of individual components without affecting the entire setup. - It should be easy to monitor the status and performance of the system at a glance. - It should be easy to remotely switch the power to a specific load. In the years since the first power supply, USB-C/PD (Power Delivery) has become a mature, ubiquitous standard for delivering non trivial amounts of power over a USB-C cable. One side effect is that _most_ proprietary power supplies can be eliminated and replaced with a USB-C/PD based solution! There is a huge market on Ali Express that is _full_ of 'aftermarket' cables that have a proprietary connector on one end and a standard USB-C/PD connector on the other end: - [Mens shaving razors](https://www.aliexpress.us/item/3256811862618176.html) - [Old school iPods](https://www.aliexpress.us/item/3256812178780212.html) - [Any DC load with a standard barrel jack or screw-terminal connector](https://www.aliexpress.us/item/3256809056849191.html) - [High Current LiPo battery chargers](https://www.aliexpress.us/item/3256808479518188.html) - [Odd shaped barrel connectors with proprietary 'smart' pins](https://www.aliexpress.us/item/3256802959425103.html) often used by older laptops and most 1L computers from brands that _also_ make laptops ... etc. Really! As long as your device uses a standard voltage (20 volts or less) and doesn't need more than ~100W, you almost certainly can replace its proprietary power supply with a USB-C/PD based solution. So that's precisely the technology I'm leveraging for this new modular rack-mount power supply system.