Re: Why I would not buy Original Prusa i3 ever again
UPDATE
One of the fuses is broken so there was some problem with current it seems. I need to get a replacement so here's my question (just to make sure). There are 2 types of fuses with numers 15 and 5 (2 of these). Do you know what's the difference between them? I need to get 5 🙂
Re: Why I would not buy Original Prusa i3 ever again
Marcin
They are standard car fuses. There is one 15 Amp and two 5 Amp fuses.
The 15 Amp fuse protects the heated bed, whereas one 5 Amp protects the motors and the other, the logic circuitry, the extruder heater and fans.
It is the last one mentioned above which has failed; the cause of failure will need to be remedied otherwise it will blow again.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Why I would not buy Original Prusa i3 ever again
That's all I needed, thanks! 🙂
Re: Why I would not buy Original Prusa i3 ever again
Marcin
Really sorry I didn't diagnose the fuse first time; maybe it was the obvious fault and I was over-thinking the situation. Apologies.
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Why I would not buy Original Prusa i3 ever again
Nah don't worry, no biggie 🙂
Re: Why I would not buy Original Prusa i3 ever again
One of the fuses went off last night again so the problem is still there and since I recently bought these couplers I think it's a problem directly related to them but... I really don't know what is the issue exactly. Any idea why these can give such outcome?
Re: Why I would not buy Original Prusa i3 ever again
Hi Marcin
Like you, I too have those couplers and have had no issues with them whatsoever. Theoretically, they should be electrically isolated so should not affect the fuses.
Was it the same fuse which blew?
If so, that fuse is for the logic, extruder heater and fans. My guess would be the heater and/or fans. Can you measure the resistance of the heater with a multimeter? Do you use the part fan while printing? Do you have any spare fans you could swap in, in place of the current ones?
Do you have anything drawing power from the RAMBo 5V or 12V rail?
It is a 5 Amp fuse; allow 1.5Amps for the logic (including the buck regulator). A 30W (4.8 Ohm) heater will draw 2.5 Amps, a 40W (3.6 Ohm) will draw 3.3 Amps. But there can be a wide tolerance (15%) with the heater, so the current draw could be higher.
You only need one of the fans to short momentarily to blow a fuse.
Peter
EDIT: Marcin, can you also please check the connections on the heater to ensure that the cables are properly separated and cannot touch.
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…
Re: Why I would not buy Original Prusa i3 ever again
Original print fan broke a while ago so I bought a replacement but it's definitely different than the one in the DIY kit. When it's at full power nozzle temp. drops by around 20 C so I can imagine it's RPM is much higher than it should. That's why I drop it to around 120 and everything is okay then.
I will check everything: cables, connections, fuses when I get back home and let you know 🙂
Re: Why I would not buy Original Prusa i3 ever again
Marcin
The print fan should be 0.06 Amp; any replacement of similar size will be about the same, but any fan could have momentary problems...
Peter
Please note: I do not have any affiliation with Prusa Research. Any advices given are offered in good faith. It is your responsibility to ensure that by following my advice you do not suffer or cause injury, damage…