Smoke and burnt smell when powering the HotBed

[aubin80]

Hello everybody,

I come there to solve a big problem with my hotbed.
I recently bought ABS Filament. In order to print it, I turned on the hot bed and the problem appeared:
- The temperature increases too fast (It reached 110°C after only 1 min)
- A burnt smell began to occur
- Smokes began to appear on the Ramps 1.4 Controller Board

My printer is a Geeetech PRUSA I3 Pro B with Mega Board and Ramp 1.4.
The HotBed was already soldered and the thermistor already stucked with Kapton tape.

Is my hotbed defective and I need to order a new one, or can I fix it by doing something special?

Thanks for the Help

Aubin

[zhangxueyou]

Where do you connect the hotbed? D8 or D10?

[aubin80]

I connected it on D8. I've even tested it in direct 12v with a other power supply (12v 5A) and the result is the same

[zhangxueyou]

Could you please take a photo, and highlight which part smokes and burnt? So that I could better understand your issue. Thank you.

[zhangxueyou]

Bad cooling might cause burning.

[aubin80]

Sorry for the late answer. I was very busy these last days.

I have finally found the problem. There was a short circuit on the heating bed.

I have bought a new one (the MK2B) and now it's working well.

For people who may have the same problem, there is also a picture wich shows the place where smokes came.