Page 703 - Basic Electrical Engineering

When windings are star connected, the line and phase quantities are
represented as shown in Fig. 8.17 (a).

Here,

When windings are delta connected, the relationships of line and phase

quantities are shown as in Fig. 8.17 (b).

Figure 8.17 (a) Stator windings star connected during starting; (b) stator windings delta connected in
running condition

Here,

If we take the ratio of line current drawn when the windings are star
connected to the line current drawn when they are delta connected, we get