11-differences between start connection and delta connections
Sl No. | Star connection | Delta connection |
1 | Two types of star connections are possible A-4-wire, 3-phase system B-3 wire. 3-phase system | Only 3 wire. 3-phase system is possible |
2 | Out of 4 wires, 3 wires are the phases and one is neutral | All 3 wires are phases in Delta connection |
3 | In Star connection, one end of all the three wires are connected to a common point in the shape of Y to form neutral | In Delta connection every wire is connected to two adjacent wires in the form of triangle.And all the three common points of the connection form the three phases |
4 | Line current and phase currents are same | Line current and phase current are different.Line current =√Phase current |
5 | Line voltage and phase voltages are different, Line voltage =√Phase voltage | Line voltage and phase voltages are same |
6 | Since line voltage is more than phase voltage, insulation required for each phase is less | In Delta connection line and phase voltages are same hence more insulation is required |
7 | Star connections are used for both transmission and distribution applications/networks | This connection is generally used for distribution networks |
8 | Since insulation required is less, these connections are used for longer distances | Since insulation required is more, these connections are used for shorter distances |
9 | Star connections are used where less starting current and starting torque is required | Delta connections are used where starting current and Torque is more |
10 | Power calculation in Start connections.
P = 3 X Vp X Ip X Cosθ
Or
P = (√3 X VL) X IL X Cosθ | Power calculation in Delta connections.
P = 3 X Vp X Ip X Cosθ
Or
P = (√3 X IL) X VL X Cosθ
|
11 | In star connections different voltage levels are used as line voltage & phase voltages are different | In Delta connections, only single voltage is used |
