black psu problem, noise and power failure  

RE: black psu problem, noise and power failure

Sure sounds like the PS is the source and not normal. 

I would hold off on additional printing because if the PS fails and produces an unacceptable voltage, other parts of the printer might be adversely effected. 

RE: black psu problem, noise and power failure

@agkirk

yes sure, i have immediately stopped the printer after second restart because i think is not safe...however I am not convinced about the reason of this problem. Hope the new one psu will work fine but what i don't like is that i can't find something similar online (you tube, forum etc)...

RE: black psu problem, noise and power failure

I ordered a

Mean Well NES-350-24 24V 350 Watt UL Switching Power Supply 120 Volt 

and I never looked back.

RE: black psu problem, noise and power failure

@swiss_cheese

did you had problems with the stock black psu from delta electronics? and what about the power panic cable with the psu you have bought? 

RE: black psu problem, noise and power failure

There was some discussion on this forum regarding the high failure rate of the Prusa 24v PS so I elected to be proactive and ordered the following:

You only need to print the case, the other parts could be salvaged from the PRUSA PS.

Modified PETG case/mount :          https://www.prusaprinters.org/prints/10432-prusa-mk3-mean-well-lrs-350-specific-mount

From  E-Bay USA
5pcs Mini Switch Rocker Switch Power ON OFF AC 250V/6A 125V/10A 2Pin   $5
M3*4-M3*60 Hex Flat Head Screws 304 SS A2 Countersunk Bolts M4*6-M4*80 ( 174007860271 )  $2
M3*4-M3*60 Hex Flat Head Screws 304 SS A2 Countersunk Bolts M4*6-M4*80 ( 174007860271 ) $2
MEAN WELL LRS-350-24 350.4W 24V 14.6 Amp Single Output Switchable Power  ( 133404275174 )$40 (N0w Cheaper on Amazon)

From Amazon:

PSU Power Panic V 0.4 High Voltage with 10A 250V Fuse Switch and Cable,Power Supply Power Detection Module Socket for Prusa i3 Mk3 MK3S 3D Printer
Brand: POLISI3D

RE: black psu problem, noise and power failure

I just reused all the parts from the printer. I wired the mean well and used it to print a case for itself, once done I disconnected it, rewired it, and was good to go no extra screws or parts needed that weren't printed. its been running flawlessly day in and day out since August 13, 2019.

RE: black psu problem, noise and power failure

The silver 24v psu appears to have had  more failures than the black powersupply

regards Joan

RE: black psu problem, noise and power failure

@lore2688

The one that burned out was a silver one on an MK3, Prusa sold me the black one for $99 with all the parts to upgrade its attachment to the frame and wiring, it was taking to long to get here. so I ordered the Mean Well from Amazon, I have had zero issues with it and its quiet.

the one Prusa sold me sits in the box it was sent in and I have never looked at it since the day it was received, or even unwrapped it, until now to take this photo.

My power panic wire hooked up just fine to the Mean Well and everything works as its supposed to, and if I ever need it, I now have a Prusa PSU laying around.

This is the wiring schematic for the mean well I posted. I did check the connection on my MK3s, since I used this on my MK3 and the hook up looks the same, that said, (you should confirm for yourself all information).

If you feel comfortable with this information and your looking for a case for the Mean Well, there are many posted online for free for this model, with attached and detached options for printing in an enclosure. also I suppose I should mention if your printer is really new you might want to contact Prusa and see if they will replace it for free. 20 hours ? you shouldn't be having PSU problems they "Maybe" they could trouble shoot it for you.

Anyway I hope this helps and good luck, I'll keep an eye on the post to see how it goes.

RE: black psu problem, noise and power failure

Posted by: @swiss_cheese

@lore2688

The one that burned out was a silver one on an MK3, Prusa sold me the black one for $99 with all the parts to upgrade its attachment to the frame and wiring, it was taking to long to get here. so I ordered the Mean Well from Amazon, I have had zero issues with it and its quiet.

the one Prusa sold me sits in the box it was sent in and I have never looked at it since the day it was received, or even unwrapped it, until now to take this photo.

 

My power panic wire hooked up just fine to the Mean Well and everything works as its supposed to, and if I ever need it, I now have a Prusa PSU laying around.

 

This is the wiring schematic for the mean well I posted. I did check the connection on my MK3s, since I used this on my MK3 and the hook up looks the same, that said, (you should confirm for yourself all information).

 

If you feel comfortable with this information and your looking for a case for the Mean Well, there are many posted online for free for this model, with attached and detached options for printing in an enclosure. also I suppose I should mention if your printer is really new you might want to contact Prusa and see if they will replace it for free. 20 hours ? you shouldn't be having PSU problems they "Maybe" they could trouble shoot it for you.

Anyway I hope this helps and good luck, I'll keep an eye on the post to see how it goes.

Oh, thank you for these information! I’ll keep it in mind for the future...tomorrow i’ll receive the new one psu from prusa and then i’ll try it immediately..if all is ok i have solved it but if not i to find a solution and maybe this can be one (even if my printer is new and i want that she work fine because i have payed it!)..just i don’t have well understand where i need to connect the power panic cable on the meanwell..

RE: black psu problem, noise and power failure

I would never repair a PSU unless you are an electrician or engineer.  The resulting fire is not worth it.