Difference Between Single Phase & Three Phase

The power supply system is mainly classified into two types, i.e., single phase and the three phase system. The single phase is used in a place where less power is required and for running the small loads. The three phases are used in large industries, factories and in the manufacturing unit where a large amount of power is required.

One of the major difference between the single phase and the three phase is that the single phase consists one conductor and one neutral wire whereas the three phase supply uses three conductors and one neutral wire for completing the circuit. Some other differences between them are explained below in the comparison chart.

Comparison Chart: Single Phase V/S Three Phase

• Comparison Chart
• Definition
• Key Differences

Basis For Comparison	Single Phase	Three Phase
Definition	The power supply through one conductor.	The power supply through three conductors.
Wave Shape
Number of wire.	Require two wires for completing the circuit.	Requires four wires for completing the circuit.
Voltage	Carry 230V	Carry 415V
Phase Name	Split phase	No other name
Power Transfer Capability	Minimum	Maximum
Network	Simple	Complicated
Power Failure	Occurs	Do not occur
Loss	Maximum	Minimum
Power Supply Connection
Efficiency	Less	High
Economical	Less	More
Uses	For home appliances.	In large industries and for running heavy loads.

Definition of Single phase

The single phase requires two wires for completing the circuit, i.e., the conductor and the neutral. The conductor carries the current and the neutral is the return path of the current. The single phase supplies the voltage up to 230 volts. It is mostly used for running the small appliances like a fan, cooler, grinder, heater, etc.

Definition of Three Phase

The three phase system consist four wires, three conductors and one neutral. The conductors are out of phase and space 120º apart from each other. The three phase system is also used as a single phase system. For the low load, one phase and neutral can be taken from the three phase supply.

The three phase supply is continuous and never completely drops to zero. In three phase system power can be drawn either in a star or delta configuration. The star connection is used for long distance transmission because it has neutral for the fault current.

The delta connection consists three phase wires and no neutral.

The star connection of the three phase allows the use of two different voltages (i.e., the 230 volts and the 415 volts). The 230V is supplied by using the one phase and one neutral wire, and the three phase is supply between any two phases.