Why does delta connection have no neutral connection?

Lets compare between a star and delta connection in 3-phase power types. In a star connection, there are 6 connections (A1, B1 and C1 being the outer arms of the 3 armed star and at the centre, A2, B2 and C2). The center is called the neutral or star point which carries out the any unbalanced current loads through its connection. That is why if you lose out the neutral point in a star connection, there will be an overflow of current through to the loads. The loads also take in more current, generating much more power and could damage the appliance you are using and the components the line current is connected to, since excess heat and overworking may result.

In a delta connection, the connection has only 3 and on a piece of paper it is sketched as the connections being joined arm to arm. One side is A phase, B phase and C phase. Getting to the point, a Delta connection does not have a earth wire because the live voltage is always the same throughout the connection. Since phase and line voltage are the same and constants. It also means the line current will change without affecting other components within the circuit. Balanced Delta connected circuits or loads can only have their power supply sourced from a star connection and a balanced Star load can only have their voltage supply come from a delta connection.

With a delta connection, the phasor sum of the three line currents is zero, whether the load is balanced or unbalanced, so no neutral is necessary.