brand new control board power up caution

[Jerry Roane]

I have a brand new dual extruder board rev A+ and I power it up with 12 VDC and it turns on, or if I plug in the USB cable it turns on. My fear is if I power up both the 12 VDC connection at the same time as plugging in the USB wire will those two power connections fight each other and cause a burn out? Is there anything I need to do to power both the 12 VDC connection and the USB cable? Is there a jumper and is there a set of instructions for starting up my new A+ revision board? The display works so I assume it has some kind of firmware installed from the factory.

[William]

Hi, our drawing is open, you can refer to this:https://github.com/Geeetech3D/Prusa_I3_ ... evA%2B.pdf

[_kaktus_]

Hi.

In theory, you don't have to do anything.

The controller board has a mechanism to detect external power supply and automatically disconnect power from the USB port.

[Jerry Roane]

Thanks I powered it up with both the 12VDC and then the USB and it did work. No smoke. I am converting a Printrbot simple metal that died from a static electric zap. Now it appears that the connectors are all similar but different enough not to just plug in. The schematic really helped even though pin one designation of all the connectors is hard to determine other than buzzing out the pins that go to ground. Powering up with just the 12 VDC connected lights up three green LED lights. Plugging in the USB flickers a yellow LED over by the crystal in a repeatable time pattern then it goes off. This board allows me to add another print head (color) to my obsolete Printrbot simple metal.

[_kaktus_]