Several fan failures

[rrctelles@hotmail.com 0]

Hi guys,

I'm new to the forum and to 3D printing as well. I just got my UM2 last wednesday and have been trying to play with it, but I have been having problems from day one.

First of all, my printer came with a defective left fan. I tried to get a replacement but only managed to get a different model. The guy who sold me it mistakenly gave me a 7V fan instead of a 12V fan. As I connected it both fans died out and apparently my fan pwm connector fried (although there were no visible signs), since the 7V seems to have pulled a lot of current.

So...

Question 1: Is it possible that the pwm output fried? I've probed it with a multimiter and nothing connected, but sending 100% fan speed from the menu, and got 20V. Nevertheless the replacement fans I got did not work. I tried also setting the pwm to 50% and connecting the working fan to it but it did not work as well. If it fried, can it be fixed, is it fused, etc;?

Later I got two 12V fans and connected it to a 24V outlet on the board in order to get anything printed, since without the fans the prints were coming out to hot and deformed. It's been working ok for the last couple of days, but today suddenly the back fan stopped working mid print. :cry: I've read that it stays on as long as the printer is on, and some people even complained about the noise.

Question 2: Can it be that this fan was damaged because I plugged the others in the power outlet? I tested the fan externaly and it really is the problem (the blue and orange wires are supplying 5V normally). I can't believe I'm having a second fan failure in a week for no good reason...