...difference between a 220v 3phase power supply...

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Answer by stephen1231
Submitted on 1/21/2004
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There is a great deal of difference between a three phase and a single phase circuit. Both provide alternating current with the voltage or current following a sine wave that is starting at zero rising to a maximum say 220 volts then decreasing to zero followed by the voltage rising again but in a negative direction or minus 220 volts. In a single phase circuit this just keeps repeating based on the frequency say 60 hertz) that is 60 times a second. In a three phase circuit this occurs with each phase (three) the voltage rising falling going negative and increasing in the opposite direction. At any instant there are in fact three different voltages impressed on the three wires. To sum it up any device, say motor designed for single phase operation must be used on a single phase circuit. A three phase motor can only run on a three phase circuit

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Question by DavMar
Submitted on 10/6/2003
Related FAQ: Electrical Wiring FAQ (Part 1 of 2)
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What is the difference between a 220v 3phase power supply compared to a 220v single phase power supply?

Answer by Jo
Submitted on 11/15/2003
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Simple explanation I hope. If you connect each phase of the 3phase cct via a load to neutral (using 3 separate loads) you have created 3 separate single phase power supplies. Hence the terms 3phase single phase

Answer by cantyousee321
Submitted on 3/10/2004
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A three phase is 3 ungrounded conductors (Hot wires)Flowing at 120 electrical degrees apart, 3 alternating currents there are no grounded conductors (neutral wire). A single phase is 1 ungrounded conductor and 1 grounded conductor.A three phase motor does not need a start or run capacitor because there is 3 currents bombarding the poles in the motor at 120 electrical degrees apart so the magnetic field is strong enough to cause the rotor to make 1 revolution and follow that field.Where as a single phase motor needs a start or run capacitor to get the rotor to spin unless it is a shaded pole or split phase.But that is a question for another day.

Answer by tadek
Submitted on 4/1/2004
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There is a difference in efficiency also.Single phase Power say 100 amps at 220v would equall(P= IV) or 220100=22,000 watts. Now that same current and voltage utilising 3 phase would equall (P=IV1.73)or 1002201.73=38,060 watts.

Answer by femi
Submitted on 8/1/2006
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what answer

Answer by Nancy
Submitted on 10/18/2006
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Question: so if a heater I'm interested in buying says we should have 3 phase electricity, I can't use it unless I have 3 phase electricity, then?

Answer by tattoo
Submitted on 2/9/2007
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also there is less amp needed higher the voltage the low the amp

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