Introduction: Variable DC Power Supply - USB-C

By https://www.youtube.com/channel/
About: I love designing, building, hacking and modifying.

I had a benchtop DC power supply that recently died on me. I had two paths I could take: buy a new one or build one.

I decided to build something that was smaller and more portable - as I wanted something I could quickly transfer from my garage shop to my office.

Supplies

Here are all the parts you’ll need:

  1. Variable power supply: https://amzn.to/3K4xblM
  2. Banana plugs: https://amzn.to/47Mar3N
  3. 16ga Cable: https://amzn.to/4n6bcJL
  4. Ring terminal connectors: https://amzn.to/4pQWSH4
  5. USB-C PD Adapter: https://amzn.to/465vuNA
  6. USB-C 100w Plug: https://amzn.to/4n7b4dd
  7. Screws: https://amzn.to/3IpvheV
  8. Foot pads: https://amzn.to/42zZEWS

Here are the tools you’ll need:

  1. 3d printer: https://amzn.to/4mjKX1q
  2. Filament - https://amzn.to/3d3kRBN
  3. Tool kit: https://amzn.to/4mfbBZ7
  4. Wire stripper: https://amzn.to/4nDx3IC

These are amazon affiliate links. I may make a small commission from your purchase (at no cost to you!).

Step 1: Print Parts

Print one of each part. I printed in the orientation shown.

Attachments

Step 2: Install the USB PD Board Into the Rear Panel

  1. Set the switches as shown in the image - this will allow 20vdc to be sent
  2. 1 - On
  3. 2 - Off
  4. 3 - On
  5. Bolt the USB-C Clamp down to hold the PD board in place.
  6. Use M2 x 8mm screw

Step 3: Create Your Cable Harness

  1. Approx 4” length (2x) of two conductor 16ga cable
  2. Wire 1: Attach ring terminals to one side. The opposite end goes to PS output
  3. Wire 2: Attach one side to the USB-C adapter. The opposite end goes to PS input.
  4. This is what the completed harness will look like
  5. Check the underside of the USB-C board for polarity - match these with the polarity of the power supply screw terminal (green).

Step 4: Install the Banana Plugs

Insert the banana plugs into the housing, then install the clamping piece, washer and nut.

Put ring terminals onto banana plugs, tighten nuts.

Step 5: Bolt Rear Panel in Place

Use M2 x 8mm screws

Step 6: Install Power Supply Into Front Cover

Snap the power supply into the front cover.

After it's installed, plug the green screw terminal into back of power supply

Step 7: Bolt Front Cover Into Place

Use M2 x 8mm screws

Step 8: Attach Foot Pads to Underside of Main Housing

Put foot pads into the recesses in the base.

The pads I used from the kit are about 1/2" in diameter.

Step 9: Done!

You made it, congrats!

Step 10: Bonus - Portable Case

I built a semi-customized case to hold everything. I didn't like the dividers that came with the case, so I designed a divider insert (see the 3d print).

Organizer case: https://amzn.to/46a1NLe

Attachments

Step 11: Thanks!

I hope you enjoyed this Instructable! Let me know if anything is unclear and I'd be happy to answer any questions you may have.