Brand new Prusa i3 (Zonestar) PSU blew up ..

Allright,


So today I did all my wiring and everything was clearly marked on the PCB and the connectors only fit one way. Only the power from the PSU to the PCB and the Extruder temperature have terminal blocks.
Anyway, I connected the PSU to my mains (230v) and made sure the PSU was in the correct settting. I noticed a light coming on inside the PSU and I measured the pins on the PSU to be 12v.

Guess I wanted to verify that before hooking up the PCB. After disconnecting mains I waited for the PSU LED to go off and then connected to COM and VCC to the PCB. Then I powered the PSU again and it immediately blew up. No more light and breakers blew out also. Now the PSU doesn't do anything anymore. It doesn't give a light and it doesn't give a 12v output.

My questions, could it be that I wired something wrong to the PCB? Would that cause my main breakers to switch off? Or is the PSU bad? Why did it work before connecting the PCB? What can I do to troubleshoot?

I have looked at the printer for a while now and I cannot see anything that isn't connected the way it should (or at least how I think it should). The only thing I noticed was that the hotend has 2 red wires instead of a black and red. It doesn't seem to have a plus and a minus? The drawing on the manual also shows that so I figured it was okay, was this my big mistake? On a side note, I chose not to connect the heated bed to the PCB since I plan on not using it (I have a Wanhao Duplicator 4s and only print PLA without heated bed).

This is my first DIY-kit build. Hope you guys can help. Thanks a lot.

Edited 1 time(s). Last edit at 10/18/2015 05:50PM by MrFex.

BTW: I have been smelling the hardware and I have no fire smells. None of the terminal blocks or wires are scorched or darkened.

Somebody recommended I try to power up the board via USB since I hadn't done that at all. At this point nothing is recognized and no lights are coming on. Windows doesn't detect anything. Not sure if this particular PCB supports powering via USB.

Edited 1 time(s). Last edit at 10/18/2015 05:48PM by MrFex.

Doesn't matter about the heater wires from the hot end being both red. Can be connected either way. You need to ohm the power input terminals of PCB for a short. You do probably have a short. I the power supply should have a fuse which is probably blown.

Vcc usually indicates a 5V input. If you connect 12V it will blow up the chips on the board. You'll need to replace the board and possibly the psu, identify the inputs with the correct voltages and polarity. Check the psu output voltage, some psus can be adjusted.

When the breaker blew out, you must have had a serious problem in the PSU. The inrush current into the controller was enough to start a "self-destruction" chain of events.
-Olaf

Thanks for your responses.

IMQQMI:

I have checked the output on the PSU with a multimeter before hooking it up to the PCB and it showed 12v. The output is labelled V+ instead of VCC, my bad.

Olaf:

I am no expert on electronics but I *think* that the wiring on the PCB should never cause the entire PSU to fail, let alone short the breaker. Hopefully that means that the PCB is still fine, but I don't know how to verify that.


Does anyone have an explanation for the fact that the PSU didn't blow up when the PCB was not connected. It showed 12v but obviously no power was being drawn.

Hi everyone,


Just wanted to give an update, last night I sent a mail to the webshop about this problem. This morning a reply was waiting for me, they suggested getting another 12v power supply somewhere and testing the PCB so that they don't have to ship it out if not necessary. To my satisfaction I discovered that I could power the PC and all the motors using a 12v 5A power supply. Of course I didn't do much except test each motor and sensor. Great news for me. Hope the new PSU gets here soon so I can actually print something. Thanks for all the help