Snap on HW-688 (24v to USB 5.2V/5A for 4040 i.e. Ender3 + OctoPi)

thingiverse

Found this inexpensive DC/DC covnerter to power my Raspberry Pi that runs OctoPi , and made a snap fit set of clips and cover to mount it to the 4040 profile on the Ender 3 Pro. Pending thermal imaging after installing but in a slightly cool room its barely warm to the touch after being idle all night and after a print job. It did get quite warm when bench testing with 3A continious load - like 40C over ambient flat on a desk. Vertical mounting helps a lot but my phone died so can't use the Seek Thermal imager for a while. Pi runs stable, no undervolt errors. Even at 3A load the output stays at 5.17V in testing. Very conveient it has full size USB port to connect Raspberry Pi. It does appear the board is not using the overcurrent protection feature of the chip however. Beware tight tolerances for snap fit, might not work well with your printer.