110volt versus 240 volt

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In Australia we have 240 volt single phase on domestic houses ( a couple of older houses you will find 240 volt 2 phase) and 415 3 phase all at a nominal 50 hertz.I notice in USA you have 110 single and I think 220 3 phase  at I think 60 hertz.Could some one explain the pro's and cons of the two ?Also at an extra 10 hertz does that help at all on AC?A good guess is better than a bad measurement
Reply:What we have here in US is 110-120v and 208-240v single-phase for most residential buildings.  For commercial and agricultural we have the aforementioned, plus 220-240v and 440-480v in both single and 3-phase and 575v.  All at 60 Hz.I'm not sure I understand what 2-phase is. One advantage of 3-phase over single-phase is less current (amps) on each hot wire to carry the total power to the appliance since the current is being carried by 3 wires instead of two.I don't know about the 50 Hz -vs- 60 Hz part of the question.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:motor starting on three phase is simpler... no split phase, cap start, etc..etc.  just apply power.  if it spins the wrong way, reverse any two leads.
Reply:Brett - when you refer to the difference that some houses have 240 single and some have 240 2 phase, are you saying the single phase carries all 240 volts on one hot wire and a common with the 2 phase being 2 120 volt hot wires?  In the US 240v single phase is done with 2 120v hot wires.  I have always wondered why it wasn't called 2 phase since technically it would have to be 2 separate 120 volt phases to get the potential between them to be 240...
Reply:Originally Posted by TubularFabI have always wondered why it wasn't called 2 phase since technically it would have to be 2 separate 120 volt phases to get the potential between them to be 240...
Reply:In much of Europe and many parts of Asia the voltage is 240 and the line frequency is 50 Hz. There is a huge safety factor between 120 volts and 240 volts. In the 240 volt system I can't remember if one side is grounded or not. As for the frequency, power transmission is more efficent at higher frequencies, but as the frequency becomes higher the energy begins to travel on the outside of a conductor rather than through it. This is why on high frequency transmission lines for radio, hollow tubing is used rather than solid conductors. The inside of the conductor would be wasted as the energy would be traveling on the outside of the conductor - this is called skin effect.The 60 cycles would be a little more efficient than the 50 Hz.Also, in the US they claim the the hum found in equipment is less objectionable at 60 Hz than at 50. Modern construction has probably eliminated the hum concern. You are more apt to burn out inductive equipment - transformers and motors - if you operate 60 Hz on equipment 50 Hz than the other way around. You can find equipment, however, that is designed to work on both system voltages and frequencies.
Reply:Originally Posted by BrettIn Australia we have 240 volt single phase on domestic houses ( a couple of older houses you will find 240 volt 2 phase) and 415 3 phase all at a nominal 50 hertz.
Reply:Why do I ask?Just interested wizard69, (certainly not thinking of moving )   Thanks for the replies allA good guess is better than a bad measurement
Reply:I spent 3 1/2 years in Germany where power is 220V/50hz. We had to use transformers to use our US tv's and such. The TV, VCR and such all worked great, but the record player on the stereo didn't. It spun just a little slower and you could tell it. It didn't affect the cassette player. No problems with the microwave either.The difference between art and craft is the quality of the workmanship. I am an artist.
Reply:Originally Posted by BrettIn Australia we have 240 volt single phase on domestic houses ( a couple of older houses you will find 240 volt 2 phase) and 415 3 phase all at a nominal 50 hertz.