Polarized AC Power Outlets?

One of the wires which carries the current is the Line (often called live or hot) and the other is the Neutral.

It is important to know which one is which.

Some older appliances, like toasters or lamps, had the outer case connected to the Neutral or Return connection, and the hot power would just go to the switch and the heater or light elements. However, if you plugged the toaster in the wrong way, the outer case would become energized instead! It would still work, but it would shock you. I had my toaster sitting on a stove once (it was well grounded), and if I put one hand on a bare metal place on the stove and the other hand on the toaster, I would get a shock. Luckily, I didn't die, nor did I place anything metal on the toaster, which would have caused sparks. I don't know if the toaster was faulty or designed that way, but I certainly plugged it in the proper way after that.

These days, they can't use the outer case for power conduction, but a lot of times it may be connected to the third prong (earth), which is the case with your PC. However, if somebody gets a lamp or old fan or something at an antique shop or second-hand store, you could be in for a shock if it's plugged in wrong. Or imagine if you have an old lamp that's plugged in wrong, sitting on top of your PC - you'll blow a fuse at least.

interior the U. S., electric modern-day flows at 117 volts nominally, and has 2 "warm leads", one is grounded and the different connects interior the path of the wiring to the capacity source. the grounded lead is the great component of the polarized plug and there for secure practices , to apply with double insulated kit ( that equip that has purely a 2 pronged plug). the great component of the plug will pass directly to floor if a short circuit happens, keeping you from marvel via tripping the over modern-day gadget , be it a fuse, breaker ...in spite of. this is the minimum secure practices deemed appropriate via the national electric code, there are greater constructive yet greater high priced concepts at the same time with GFCIs ( floor Fault Circuit Interuptors) desire that helps.