American personnel arriving at Mildenhall or Lakenheath need to be careful when connecting their imported computer equipment to the power sockets in UK homes. The US and the UK both use alternating current, but US power is 115 Volts and UK power is 230 Volts. This means that if you plug an American desktop or tower computer into a UK power socket without making any adjustments, the computer’s power supply will probably be fried. Fortunately this is usually as far as the damage goes, and more critical parts of the computer system, such as the motherboard or the hard drive / solid-state drive, usually survive unharmed.
If you feed 230 Volts into a 115-Volt power supply, you might think that the only damage would be the power supply’s internal fuse. Unfortunately the protection circuitry in run-of-the-mill power supplies is not that great, and components other than the fuse get damaged. So even if you open up the power supply and replace the fuse, or a self-resetting fuse recovers automatically, the power supply will still no longer work. Fixing the power supply is usually impractical and uneconomic, so it’ll nearly always be necessary to obtain a new one. However, it’s possible to get hold of power supplies quite cheaply.
Some power supplies are dual-voltage, with a small red switch on the back that allows you to select either 115 Volts or 230 Volts. If you slide the switch to the ‘230 Volts’ position in the UK then the equipment should work fine when you plug it in. If it doesn’t then there might be something else wrong with the computer, possibly caused by heavy handling in transit. Give me a call and I’ll be happy to help.