The Bottom Plate
The bottom plate of the X250 acts both as a power distribution board and as structural support for the frame. The power distribution carries current for both the ESC's and the LED's that on each arm. There is even a little tiny switch soldered into the plate so you can turn the LED's on and off. The first thing I did was align my arms with the holes on the bottom plate and secure them in place with the screws and nylon standoffs provided.
Note: The bottom plate came with the power cables already soldered into the VCC and GND ports.
Note: The bottom plate came with the power cables already soldered into the VCC and GND ports.
I repeated this for all four arms and tightened down all the bolts to make sure those LED solder mounds made good contact with the bottom plate.
The bottom view of the arms and the bottom plate: