Screwdown Minimal Power Supply Cover
by buildrob, published
This is a fully parametric design of a power supply terminal cover to fit the 12V DC power supplies commonly used on many RepRap printers today.
The different thing about this design is that it is secured by screwing down the cover into one of the low voltage terminals (V-) of the supply with a M4x16mm screw.
The advantage of using this screw down approach to secure the cover is that the cover clearances can then be far larger than if using a friction or press fit.
Since there are many different makers of power supplies of this type and all are slightly different - then hopefully this screwdown version should be more likely to fit your supply without modification (if not then you can always modify the parametric openscad source file yourself).
1) Print cover.
2) Remove central terminal screw (V-)
3) Fit cover.
4) Insert M4x16mm screw and washer though center hole and screw into terminal block.
There is no danger in touching the V- terminal or accidentally shorting it to the casing. In fact many builds recommend that you connect V- terminal to the Ground terminal to ensure that printer is properly earthed. [It's a floating supply otherwise.]
I have included two versions of the cover. One (_for_lugs.stl) has a 4mm lip and is for use if you are using mains cables with crimped connector lugs (which require a little more clearance). The other one (_no_lugs.stl) has a lower 5.5mm lip which is better if you are not using crimped lugs on your cables.
Regardless of whether you are using crimped lugs or not, you should always use strain relief on your mains cable. Otherwise movement of the cable backwards and forwards, or sharp tugs (e.g., someone tripping over the cable) can result in a mains cable being exposed. The strain relief can be as simple as a cable tie through the grille holes (although a plastic P-clip would be better).
In hindsight, even the tabs on the side are actually fairly superfluous - the cover is held sufficiently in place just by the terminal block itself. So just chop them off if they cause you any problems.
This is a guide as to what worked for me. Please consider mains electricity safety for yourself!