How do I convert a 240v outlet to 120v?
Simply so, can you turn a 110 outlet into a 220v?
Converting a 110-volt outlet to a 220-volt outlet requires extensive rewiring and most building codes would require inspection. There is an alternative available: Use a voltage step-up converter.
Similarly, what happens if you plug a 120v appliance into a 240v outlet? If you plug an 110V appliance in 220V outlet (same as 120v to 230v, 240v) you can only hope that some protection device disconnects the power to the appliance. Otherwise: It is current that is your enemy, a piece wire that is warm at 110V (120v) will turn into a fuse at 220V (230v, 240v), all other things being equal.
Likewise, can I use 125v outlet in place of 250v?
You have to mach the plug and receptacle to the voltage and amperage of the device. If it's 110-120V, use the 125V. If it's 208-240V, use the 250V. If heat dissipation is an issue, you have a design problem with the utilization equipment.
Is there a converter for 220v to 110v?
"It is both an adapter and step-down converter" - by Grace S. As an adapter, it comes with the usual US, UK, Europe and AUST prongs. As a converter, it can convert 220V (Europe, China, etc) to 110v, not the other way around though. There is a switch to select the adapter or converter mode.