# Difference between star and delta connections in Electric Circuits

### Difference between star and delta connections in Electric Circuits

In this short post let us discuss about the Difference between star and delta connections. Before proceeding further, let us refresh about the star connection and delta connection.

Between three terminals A, B and C we can connect three resistors in the following two methods.

1. Star connection
2. Delta connection

In star connection, one end of each resistance is connected at one point ( which is called as star point) and the remaining three terminals are connected to A, B and C. Since it looks like a star, this type of connection is called as star connection.

On the other hand, in delta connection, the three resistances are connected end to end so as to form a triangular or Delta shape.

In some complex electrical circuit, the total resistance calculation will become simpler if it is in star connection.
In some other circuits, the resistance calculation will become simpler if it is in delta connection.

#### Comparison of Star and Delta Connections

• Loads connected in delta dissipate three times more power than when connected in star to the same supply.
• For the same power, the phase currents must be the same for both delta and star connections (since Power P=3IP2 RP).
Thus the line current in the delta connected system is greater than the line current in the corresponding star-connected system.
• To achieve the same phase current in a star-connected system as in a delta-connected system, the line voltage in the star system is √3 times the line voltage in the delta system.
• Thus for a given power transfer, a delta system is associated with larger line currents (and thus larger conductor cross-sectional area) and a star system is associated with a larger line voltage (and thus greater insulation).