
Frequency Differences
#1
Guest__*
Posted 02 September 2005 - 12:06 PM
Please, I Need a Help!
What is The Difference between The frequencies 50 HZ & 60 HZ? and which one is better? and why?;q
#2
Posted 02 September 2005 - 04:11 PM
The one that is better is the one that is supplied by your utility! Other than that, it makes no difference except that if you are in a country that promarily uses 50Hz, it will be dificult to get 60Hz motors, and vice versa. Stick with whatever is the local standard.
#3
Posted 03 September 2005 - 07:38 AM
The two standards have been adopted in different regions and the choices have been based on a number of characteristics.
All lines have inductance. If we pass an AC current along a line, it will be affected by the reactance of the line. A high reactance will result in a higher line loss. Increasing the frequency on a given line will increase the voltage drop on that line. From a line reactance perspective, a lower frequency is desirable.
Underground Cables have capacitance. Higher frequencies result in higher capacitive currents. For cables, lower frequencies are preferable.
Supply systems require generators and transformers, both of which have iron cores. As the frequency of the supply is increased, the volume of the iron reduces reducing the size of the transformers, generators and motors. From an "iron" perspective, a higher frequency is desirable. - aircraft use 400Hz systems to keep the size and weight of motors and transformers down.
The frequency of the supply gets cross coupled into communications systems. The higher the frequency, the greater the interference problems.
These are some of the issues involved in frequency selection.
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#4
Guest__*
Posted 03 September 2005 - 09:00 PM
Have a Good Day

#5
Guest__*
Posted 04 September 2005 - 12:30 PM
I think the difference between the two systems is historic rather than technical. It was the Genius Nikola Tesla who invented the 3-phase system by the end of the ninteenth century and he developed the 6-Hz system in USA and it was adopted later across the Americas. However, in Europe, the Germans applied 50 Hz and there is no proof that it was selected based on calculations.
Technically speaking, I believe the 50Hz system is more efficient in big countries where transmission lines are long. Practically speaking, the USA uses 60 Hz which is contradicting engineering calculations.
#6
Posted 04 September 2005 - 06:05 PM
In Germany, AEG decided to get on the bandwagon for AC power, but selected 50Hz for the simple reason that it seemed to fit better in a metric system. Everyone else in Europe followed suit, and the fact that much of the rest of the world at that time were colonies of European countries, they ended up with the same as well.
#7
Guest__*
Posted 24 November 2005 - 10:09 AM
One advantage of 50Hz is that generators can be built bigger than with 60 hz systems
Fred Starr
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