Can you get a 3 phase supply by using three single phase supply?

Answer 1

Not that easily. A three-phase system can be broken out into three separate single-phase supplies, but in the three phase system the three supplies must have the right phase relationship, spaced apart in time by one third of a cycle always.

The reason for that is that we can consider each separate supply as having a live wire and a neutral wire. With a 3-phase system if the three neutral wires are comined into one neutral wire, the current in that single neutral wire is zero - provided all three live wires supply equal currents and the right phase relationship is maintained.

Answer 2

Yes - But only if the three 1 phase supplies are all different phases. if they are the same phase - NO. In other words, to use single phase supplies to supply three phase current you must be able to phase shift the single phase supplies so they are 120 degrees out of phase with each other. If your supply is not able to do this, you would need to purchase some phase shifting Transformers. In general, such a method seems very atypical, non ideal, and problematic to me.

Answer 3

By using only two of the three phases. they would be 120 degrees out of phase. If you're looking for two phases 180 degrees, out, just use one (the phase and return path are 180 out from each other).

Answer

A two-phase system has phase voltages which are displaced by 90o to each other and, therefore, cannot be supplied from a three-phase system, whose phase voltages are displaced by 120o to each other.

Answer 4

Typically you need to approach your power supply company and request connection to all 3 phases.

The average domestic property will not have all 3 phases brought in from the street, this is in part a means of avoiding accidents. When multiple phases are present in a property there is the possibility of connecting between them, which when done improperly can be dangerous. Some power companies also use the phases to wire up different sections of a street, thus placing x houses on each phase to roughly balance the load on each phase. You may find that all 3 phases are not immediately available in the wiring directly outside your property.

Answer 5

This is normally achieved at the low-voltage end of the supply chain, where the low-voltage secondary of the substation transformer is star-connected and the star-point is grounded to provide a connection for the neutral wire.

Answer 6

The line and neutral are two of the phases , the third phase is formed by connecting a suitable capacitor from either of these wires to create a phase shifted third output. The only problem with this arrangement is the shift in the phase is dependant on the load and sometimes several capacitors are switched in as the load changes to solve this problem.

Answer 7

A two phase supply is old technology that is not used any more by the utility companies. If you are referring to two legs of a three phase system, in the electrical trade this is referred to as single phase.

Three phase power can be split into single phase power. A three phase supply has terminal points called L1, L2 and L3. By using any two of these three terminal points a single phase voltage can be obtained. For an example, you have an electric heater that requires 600 single phase voltage to operate. All that was available was a three phase 600 volt service supply. The connection would be L1 and L2 = 600 volts, or L2 and L3 = 600 volts, or L3 and L1 = 600 volts. These single voltages from a three phase distribution source, in electrical terms, are classed as single phase supplies.