OnTheGulf

Solved. Polarity of DC to motherboard was wrong, Anet A8 videos show red wire to right side terminal and it is the right polarity for the new boards with 3 green plugs and no screw terminals, but my kit had an older motherboard with screw terminals. The PCB had polarity markings on it and they were opposite what the video instructions said. I switched the power wires after reading the board so the black wire was on the right side and the machine fired up properly. When in doubt, do not read the instructions, look at the printed circuit board, some nice designer might have left the polarity marking on it! So simple a solution yet so easy to miss when trusting instructions. Original post below. Also, on power supplies, certain supplies do need attention that the HOT side of the receptacle goes to the L (load or line) side of the power supply. In cheap supplies power is rectified right away with no attention to the AC wire designation and so it does not matter how the supply terminals are wired because it is AC, not DC, since AC wiggles back and forth between polarity only to be sorted out by either leg of the rectifier bridge as proper DC for the supply. OnTheGulf Hello All, Just built my first kit, a Anet A8, and when I plugged it into the wall there was a large spark. I had wired the power supply like the instructions by David Dan on youtube said at 5:25 the screw terminals from left to right are Line, Neutral, Ground and the power cord colors are light tan, light blue, yellow in the same order. So I checked continuity of the power cord and for USA the Line would go to the HOT, Neutral to Neutral, and Ground to Ground at the wall receptacle. The HOT blade is on the upper right looking at a USA receptacle. The continuity test showed the HOT blade of the power cord went to the light blue wire. I rewired L, N, G terminals with light blue, light tan, yellow. Anyone else see this? Meanwhile, nothing lights up. No lights on the mother board and no lcd display backlight.Anyone have an A8 in the USA who can tell me if it does not matter how the power cord is hooked up to the power supply? Thanks