What Is Switched and Unswitched Power?
Unswitched power describes power that is always on while switched power refers to power that can be turned off and on. Wall outlets as well as power jacks found on electronic components may be either switched or unswitched.
Switched power is that which must be controlled by a mechanism that allows current to flow. If the mechanism is turned to the "off" position, there is no current flow. Conversely, if the mechanism is turned to the "on" position, there is current flow. Unswitched outlets, on the other hand, have contacts that are permanently connected to the wiring and are therefore always live. It is important for users to remember that items connected to unswitched power are always connected to a power source, even if the item itself is turned off.