I am trying to install a 240v outlet. When I open the breaker box, I didn't find the grounding bar. I read some post. One post mentioned people need not to do that since I am using (Metal Clad) Armorlite Cable
which already grounds to the metal box. Another post mentioned we have to connect the ground wire since it is there. I can drill a hole and screw the wire in the breaker box. Sounds like I should do as the second post? I am little confused whether should we connect the ground wire to the neutral bar. I suppose I should not? But actually, the neutral bar is connected to the metal box.
My second question is that I am installing a 240V/20A outlet which doesn't need neutral wire, only two hot wires and one ground wire. In this case, I just need to cut the neutral wire at the outlet end, or should I leave it alone? Should I connect it to the neutral bar in the breaker box? I guess yes, even though it isn't used?
Update: The wire I am using is Solid CU BX/AC (AL Armored Cable)
https://www.homedepot.com/p/Southwire-12-3-x-25-ft-Solid-CU-BX-AC-AL-Armored-Cable-Armorlite-Cable-61023221/202935702
I already installed the breaker and the hot wire. Will connect the neutral wire. So should I connect the ground wire to the neutral wire bar?