Does using the 24V supply shorted the life of the HV supply?

Don, have you run across many, or any, LPS failures where the 24V output was unused on the LPS and there was an external 24V/5A PS used instead? I know we’ve talked about the onboard 24V possibly being capable of 2A or more but there’s an old note from the original designer of the K40 LPS rattling around in my head remembering he’d said his original LPS design was not intended to drive stepper motors. So just wondering if removing that load/heat from the current LPSs has lead to fewer failures. Thx

PS, I can move this to another thread or PM and don’t plan on debating this.

The lion’s share of failures I have seen is from bad HVT’s.
My assessment suggested that the HV diodes inside the HVT fail and or the secondary develops a HV short. Probably because of the exceptionally high voltage.

This means that unloading the 24VDC probably would not extend the life.

I have seen a dead 24V on a few but not necessarily related to loss of HV.


The idea of designing a proper Laser power supply has been sitting in my head for a while. Actual prototyping and production cost has hold me back from this project. So I guess I need to approach this a bit more creative. What about an open source project? I design the power supply on a open forum like Github and collaborators build the prototype stages and test it?

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I thought hard about it and even started a design.

  • Didn’t like the liabilities as this thing is lethal
  • The current design is not that bad so I don’t know if a new design would be that much better.
  • I think that the parts cost alone would add up to more than what you can buy a HVPS on Amazon today
  • If I am right and the HVT is the main failure item I am not sure that we could find or build a better one at a cheaper price.
  • The PIV of the doubler diode(s) has to be very high and I never found a suitable part. Alternately you have to stack the diodes and that creates a potting problem.
  • Some of the parts need to be potted for high voltage operation [HV diode and HVT] which is not an easy thing to DIY nor produce cost-effectively.

It’s easy to replace the HVT but it alone costs nearly as much as a new supply.

So after all of the above, I decided to dedicate the time to a more productive project and helping folks diagnose and fix this one.

Note; there is someone on here that was working on a design but I cannot find it again.


Yes I agree with you. Especially the liabilities as this thing is lethal.

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