Mk4 PSU margins - how much wattage is left to use?

Last Post

RSS

Luca

(@luca-9)

Member

Mk4 PSU margins - how much wattage is left to use?

Hi all

After assembling the MK4 and then enclosure I found out that you have to take the printer apart again. Since there could be cases where I need to have the printer somewhere else and transporting it with the enclosure is a hassle I omitted taking the PSU and display out.

This works, but obviously cooks the PSU. I'm planning to add cooling to it, similar to what people do with the Tukkari enclosure, see here:

https://www.printables.com/model/393123-tukkari-prusa-psu-40mm-fan

I already printed the mesh and attached a fan to it, now my question: Can I tap few mA from the 24V PSU via buck regulators to 5V / 12V or directly with 24V fans? Depending on the fans and speed I'll be running them (maybe the logic board gets one too) it's going to be around 100-300mA.

Is this fine or should I power the fans externally? How much more load can I safely add to the PSU, assuming maximum current draw of the printer?

Thanks

Posted : 22/04/2024 9:20 pm

Zappes

(@zappes)

Reputable Member

RE:

You can absolutely do that. I have my filtration system with a rather beefy 120mm 24V fan running off the PSU in parallel to my LED strips and there's never been a problem.

Oh, and would you mind sharing the model for your PSU cover?

My models on Printables

Posted : 23/04/2024 7:36 am

Luca

(@luca-9)

Member

Topic starter answered:

RE: Mk4 PSU margins - how much wattage is left to use?

Ok thanks for the answer. It would be nice though to have an answer from Prusa engineers about how much reserve is left with this model of PSU and the MK4.

The model isn't mine, but you can find it here: https://www.printables.com/de/model/393140-prusa-psu-cover-black-version