Do you have a question about the CASTLE PHOENIX EDGE ESC and is the answer not in the manual?
The socket may be installed through a panel or secured inside a fuselage.
Key in socket OR disconnected wire in socket harness = ARM LOCKED. A properly programmed and wired Edge will be incapable of arming when the key is in the socket.
Connect the white wire to the Aux Line (white wire) on an Edge ESC. Connect the red "+" wire to any servo wire with a Y harness.
Edge Arm Lock mode is a secondary safety device, not a replacement for safe practices. Requires specific configuration via Castle Link software and correct voltage.