ATX Bench PSU

thingiverse

This is a hybrid of robertguy and flash24's bench PSUs. The body is designed to replace robertguy's single-unit unit for easier wiring, especially for those with clumsy fingers. I've also added independent fusing and per-output meters from flash24's design. My intention was to attach the front panel using glue, but since I haven't done this yet, mine is held together by friction alone. However, I'm not sure how well that solution will last, so I don't recommend it. For the USB section, I used a PCB mount USB socket with a separate 5-volt feed from the ATX unit. A clip holds this snugly in place without additional fixings. You'll need to print out robertguy's rear case, and I expect you to show your appreciation for his project by giving it a like when you download it. Don't forget to visit flash24's design and give it a thumbs up too! I plan to add a step-up module to allow me to reach 24 volts on the DPS 5005 outputs, and I'm waiting for this part to arrive. If it works as expected, you'll read about it here (see update below). As there are numerous videos and instructables available, I haven't included any major wiring details. If you can't figure it out, you probably shouldn't be messing around inside an ATX PSU, as it can be a deadly place! The only wiring detail I'm mentioning directly is the "ballast" or "load" resistor I've hard-wired between 5v and ground. I used a 10-ohm, 10-watt aluminum-bodied resistor that's placed inside the original ATX case on the rear outlet grille. This allows the grille to act as a partial heatsink while the air exhausting from the case adds cooling to the resistor. As my PSU is an inexpensive one, the fan is always on, providing constant cooling. I'd like to extend huge thanks to robertguy and flash24 for their designs, which form a significant part of my version. So, thank you Rob, and merci Flash24! __________________________________________ Small update: I finally received my XL6019 boost converter module, and I set about installing it. By setting it at around 26 volts, it appears to give the full 24 volts from the DPS 5005. However, I'm wondering why - and hoping that electronics experts can shed some light on this - the indicated output current on the 5005 is reading incorrectly. For example, I connected a small 12-volt TFT video screen that draws about 900 milliamps, according to my multimeter (and the 5005 before I added the booster). But now the 5005 assures me that it's drawing only 274 mA, while my multimeter still sees 900mA. __________________________________________ Further update: I've noticed that the incorrect current reading on the 5005 seems to be limited to this particular load. However, in all other respects, it's working fine. The mystery deepens. Where's Big Clive when you need him?!