Mean Well LRS-350 PSU Case with Rear Plug for Prusa i3 Bear Full Upgrade (R3)

thingiverse

NOTE: This is a revised version of my original rear plug PSU design (https://www.thingiverse.com/thing:3180564) Although the original design performed well and fulfilled its purpose, several users reported that it tended to warp during printing. Despite not completely eliminating warping with this revised design, I have significantly minimized the issue, so you might notice a small error in the bottom of the case being slightly uneven. However, the bottom component will easily flex to fit this minor mistake. --- I wanted to use a Mean Well LRS-350 power supply with my upgraded Bear MK3, which is why I designed the case available here: https://www.thingiverse.com/thing:3111868 Some users asked about a version with the plug coming out the back of the case, so I created this design. The Prusa MK3 plug has been directly soldered to a "power panic" board. This is a small PCB that detects when mains power fails and notifies the printer controller before the 24V supply from the PSU also fails, allowing any in-progress print job to be saved. Because this board is soldered directly to the terminals of the power (IEC) socket, the layout of the case has been somewhat constrained, resulting in a large bulge around the socket. Like the side-plug version of my Bear PSU case (https://www.thingiverse.com/thing:3111868), it attaches to the frame in a manner similar to the Prusa PSU with the mounts in the Bear print list, however the "upper PSU mounts" are different (STL is included), so make sure you print those instead. The "lower PSU mount" is the same as that used for the Prusa PSU. Like the Prusa PSU case, and unlike my other design, this case has a removable bottom. I connect the mains Ground/Neutral/Load wires and 24V/GND wires to the PSU outside of the case, then slide everything together, and finally plug the mains wires into the plug and switch using needlenose pliers. **To attach the case to the PSU you will need 3 M4x8 flathead screws.** If you want to use longer screws, check carefully that the screws on the back of the PSU are not contacting the circuit board. **The brackets mount with M4x8 button head screws, just as with the original Bear parts for the Prusa PSU. Flat head can be substituted if that's all you have.** **To attach the bottom to the case, you will need 4 M3 square nuts (DIN 562), and 4 M3x8 flathead screws. Both of these can be sourced from the Prusa PSU cover.** The case has a hole in the left-hand side of the front. There is an additional component you can print, Voltage_Adjust_Guide.stl. This fits into this hole and provides a guide for a small screwdriver if you need to adjust the PSU output voltage after installation (the guide is there so that your screwdriver doesn't wander off target and short something out). As with all my designs, the Fusion 360 source file is provided so that you can easily do any customization that you find useful. --- EDIT (2019-01-27): Fixed an issue where the "foot" was inadvertently moved too far forward, and so would not line up with the frame bracket.