Voltage Differences by Country

I hope not to look politically incorrect but in the case of India it followed (its choice might be influenced by proximity and assistance of) the former USSR which had 220 50Hz.

for safety point of view 110V,60Hz is utilized

This is probably one of the most often asked (and annoying) questions in this forum...

Simplified answer: there is no technical advantage over one or the other. When electrification first began at the turn of the last century, Tesla and Westinghouse standardized on one set of parameters here in the US, mainly because Edison had already started trying to electrify cities with 110VDC. So to allow the use of the same light bulbs (Edison was the only one available at the time), they picked 110VAC since a light bulb does not know the difference between AC and DC. When Europeans caught up a few years later, they didn't have to contend with that pre-existing DC voltage issue so they decided on 220V because it made the wire less expensive for the same amount of current. It's no more complicated than that.

Most other countries in the world owe their electrification to colonial Europe or the US, so they follow one or the other. In the case of the poor Japanese, they ended up with 60Hz and 50hz on the same island because of the US having taken over after the war.

jraef: your close, a.c. the generators could be higher voltage, transported great distance stepped down to a voltage the user desired. i belive edison generators were 3 wire 110/220 volts. perry

Well yes, that's basically the reason why AC won out over DC, in spite of Edison's attempts to discredit Tesla and Westinghouse. But I was speaking to why THEY chose 110VAC at the time.

From "The War of Currents":

The competing systems

Edison's DC distribution system consisted of generating plants feeding heavy distribution conductors, with customer loads (lighting and motors) tapped off them. The system operated at the same voltage level throughout; for example, 100 volt lamps at the customer's location would be connected to a generator supplying 110 volts, to allow for some voltage drop in the wires between the generator and load. The voltage level was chosen for convenience in lamp manufacture; high-resistance carbon filament lamps could be constructed to withstand 100 volts, and to provide lighting performance economically competitive with gas lighting. At the time it was felt that 100 volts was not likely to present a severe hazard of electrocution.

To save on the cost of copper conductors, a three-wire distribution system was used. The three wires were at +110 volts, 0 volts and −110 volts relative potential. 100-volt lamps could be operated between either the +110 or −110 volt legs of the system and the 0-volt "neutral" conductor, which only carried the unbalanced current between the + and − sources. The resulting three-wire system used less copper wire for a given quantity of electric power transmitted, while still maintaining (relatively) low voltages. However, even with this innovation, the voltage drop due to the resistance of the system conductors was so high that generating plants had to be located within a mile (1–2 km) or so of the load. Higher voltages could not so easily be used with the DC system because there was no efficient low-cost technology that would allow reduction of a high transmission voltage to a low utilization voltage."

We use 120VAC 110VAC was used a long time ago but is typically 120VAC 60Hz.