GT2560 Rev A+ USB shortage

[darkside40]

Hi there,
i recently purchased a Geeetech Prusa i3 Printer along with the GT2560 Control Boards.
Assembling was no problem thanks to the great description.

Also first test if everything moves etc went well.

The problem began when i wanted to use Repetier Host like described in the manual. I plugged in the USB of the Board to my PC. It smoked, it smelled badly, Printers Display only showed blocks and continiously beeped.
After i cut power i found out that a fuse directly behind the GT2560's USB had been blown.

Also the USB Port of the PC is now damaged, how can this be? I mean it is nearly impossible to wire the board wrong.

[William]

That seems crazy!You can contact the sales for re-sending you a new one.

[darkside40]

Hi William,
bought it on eBay and trying the reach the seller.
The problems seems not to be the Control Boards itself, but a faulte powersupply which was shipped with the kit.
That put +12V to the metal case of the powersupply (thank good i didnt touch that) and +12V where also connected to PE which should not be, because it is dangerous.

That is also the reason why the USB cable became hot when connected to a PC.

[_kaktus_]

Take the computer to the service, let Geeetech cover the repair costs ...

Geeetech forgot to write in the user's manual that the electronics design combines two power sources directly together.
And this is unacceptable.
You are not the first with a similar problem.

[darkside40]

Being honest, i learned a bit of it.
First you should measure those cheap chinese power supplies before using them.
The guy of ebay will send me a new control board.

Unfortunately the Stepper drivers where also damaged.

[spamy666]

Hello,

Exactly the same thing happened to me. I'm Scared to do it again as it did also blow a port in my quite expensive computer.
What exactly should I look for when testing the PSU?