Author Topic: Warco Super Major Vario 5Volt Supply Upgrade  (Read 1746 times)

Offline Joules

  • Hero Member
  • *****
  • Posts: 1225
  • Country: gb
Warco Super Major Vario 5Volt Supply Upgrade
« on: March 19, 2019, 06:01:13 PM »
My mill has just turned a year old and finally out of warranty.   One thing that has annoyed me from the start is the awful 5v supply they fit for the digital tacho.  In effect they cascade 24V, 12V, 5V linear regulators it's an awful arrangement all mounted in a plastic box.  They run hot (note:- they are not bolted down so they don't all fry at once) and on occasions glitch and freeze the tacho.  On my todo list was swap out this crap for a far more efficient step down switching regulator, these things are cheap, very efficient and so run cool, but they expect DC in not 24VAC.  When you rectifiy 24VAC though a bridge rectifier you get 33VDC out, so pretty close to the upper limit of 35V for the regulator.

I use a lot of these in various projects and the beauty is, you can set them up on the bench prior to install.

Now rather than just rip out and throw away the whole boxed PCB, I decided to make use of the old board.   First off pull all the regulators, some track cutting and then parallel up the capacitors, not pretty but it will all live inside a steel case.  The regulator is held on the PCB with 3M double sided tape.  I am not expecting heat issues as the 3A regulator is supplying less than 200ma.  Once the PCB was modded, time to mount it back in the case.  it wouldn't be a Joule's project without some 3D printing, so the mounting plate for the board is 3D printed, the PCB is screwed onto it.  The mounting plate is stuck with 3M double sided tape inside the control cabinet.   Better to have some air flow as I do plan to run the 5v supply to other areas of the mill for future mods.  Install complete the mill was run up and tested for any glitching, nothing it just works, those caps are doing a good job smoothing the 33VDC coming off the bridge rectifier.

Despite my dislike of the old PCB it has actually turned out OK and made a neat install that saved me the time of designing and making my own PCB and keeping my scrap parts to a minimum.
« Last Edit: March 20, 2019, 02:40:12 AM by Joules »
Honour your mentors, and pay it forward.

Offline hermetic

  • Hero Member
  • *****
  • Posts: 599
  • Country: england
Re: Warco Super Major Vario 5Volt Supply Upgrade
« Reply #1 on: March 20, 2019, 05:48:46 AM »
Very nice Mod, they are so cheap it makes you wonder why they don't fit them in the first place!
Man who says it cannot be done should not disturb man doing it!