Welcome! Log In Create A New Profile


Heated bed problems on custom CoreXY

Posted by Sr_Peronia 
Heated bed problems on custom CoreXY
April 27, 2022 11:05AM

I'm gonna write the best I can my problem. I built a Hypercube CoreXY, it's not my first printer but is my first Arduino + Ramps 1.4. The thing is all on the printer works fine except the heated bed. The configuration is an Arduino Mega 2560 + Ramps 1.4 + Drv8825. I get a CR10 HB 300x300 12V.

In first place I used an ATX PSU that I had lying around and works fine until I connected the HB to the Ramps, magic smoke appeared but when I checked it was from the 16u2. The Arduino keeped running a while without HB, but eventually died, the 5v rail is shorted.

I decided to start from zero, I bought a new Arduino Mega 2560 and a new PSU Switching 12v 30a, just in case, I added a mosfet to the HB too. I connected everything and works great without the HB. Now, when I tested the HB, again problems, the negative wire from the PSU to the mosfet heats up a lot so I stopped instantly.

The printer works excelent except the heated bed, and at this point I have tried everything in my mind. The resistance of the bed is 1.2 Ohm so I think is fine and not shorted. The PSU is correctly wired. I used 10 AWG wires for the external mosfet just in case but it didn't work.

I tried using PID and BANG-BANG configuration on Marlin but nothing changes... And at this point I'm a little scared of test the bed without a guidance or safety advices. I can't figure out where the problem can be. I suspect that is the HB itself but I don't know how to tell, even when the resistance seems to be good, maybe there is something else.

Well this is the story, sorry if something it's not very clear. If you want to help me ask me everything you need please. Thank you and greetings.
Sorry, only registered users may post in this forum.

Click here to login