DIY Bench Supply
This project started as me trying to fulfil a need for a reliable and convenient power supply and wanting to learn some lessons along the way. I designed the project in sketchup and then proceeded to go through various stages of construction. There were a few design changes along the way but nothing major. I decided to add an external voltage probe and a switch to allow voltage measurements either from the ammeter or ground.
Power Supply Design
As my first project i have learnt a lot and would certainly do things differently in future. Aluminium bending is easier than i expected but getting a good finish is difficult. Brushing of aluminium must be done first then the piece must be kept scratch free. Its also very important to allow room for cabling. I assumed that the wires would all be flexible enough that i could just put them where i needed them but the need to make them quite long (in order to fix them in easily) combined with the quantity of wires in this supply meant that i could barely get the thing closed at the end.
Desk Lamp – The power resistor is effectively wasting energy and i would like to replace it with something slightly more functional. I have some cheap power LEDs that i bought on ebay and one of these should draw enough power to be able to replace the power LED. I plan on buying a goose-neck lamp, modifying it with an LED and attaching it to the side of the power supply.
Side Grills – The original design had perforated aluminium to act as side vents on the case. I haven’t put these in yet but plan on doing in the near future. These are purely aesthetic.
Version 2 – Thanks to all the comment on hackaday I’ve already got ideas forming for a 2nd version. I like the idea of modifying the PSU circuit to give a higher output (~48v) and then using various regulators for the outputs i need. I also want to come up with a current limiter, but i’m not sure of how to do this. If anyone has ideas then please leave a comment.
Kit version – I did consider this in the first place but comments have got me thinking again. It would be good to make this into a kit that simply bolts on to a standard PSU. The design would have to change a bit to acomodate the standard ATX screw hole locations but i’m sure i’m up to the task.