Covers for Slim 12V 30A Power Supply with Fuses

thingiverse

I used to rely on a standard 12V/30A power supply for my 3D printers and laser cutters, but I wanted something more convenient. So, I designed a simple cover, then an improved version, and finally created one with separate automotive fuses for each output connector. Recently, I came across a compact "mini" version of the same 12V/30A power supply that's roughly half the size of the standard version - it measures only 222x69x40mm. Besides its smaller size and lower price, I like that it has the 230V AC connector on the rear end well separated from the 12V DC connectors on the front end. This project uses a similar approach to my previous versions, but for the compact power supply. At the AC end, it features a standard 3-terminal IEC320 C14 AC socket and a 15x10mm or 21x15mm KCD1 rocker switch. The DC end provides 12V output on two female Molex 19-09-2029 sockets and an optional 3-digit LED voltmeter, with each of the 12V output terminals protected by its own medium size automotive fuse. There are two holes on top of the DC cover - one for the power-on LED (I used a small piece of transparent 3mm filament as an optical conductor to bring up the light from the LED on the bottom of the power supply) and another to allow accessing the potentiometer for fine-tuning the output voltage. You can also unsolder the LED and trimpot from the PCB of the power supply and reposition them directly at the level of the holes, but doing so will void your warranty and is potentially dangerous. The fact that the connectors are located on both ends means two smaller covers instead of one bigger one - which makes them easier to print because of reduced tendency for warping. Each cover is attached to the corresponding end of the power supply by four M3x10 screws, which you'll need to drill into the protruding aluminum walls. You'll have a choice to secure the screws with M3 nuts inserted into the corresponding nut traps inside the plastic covers or tap an M3 thread directly into the aluminum walls. If you choose tapping, you'll need to predrill 2.5mm; otherwise, use a 3mm drill for the holes through the aluminum. The provided OpenScad source file is fully commented and configurable, with ready-to-print STL files available for variants of the AC cover (15x10mm or 21x15mm switch) and DC cover (with or without digital voltmeter).