This document discusses star and delta connections in 3-phase power systems. It provides symbols and diagrams to illustrate star and delta configurations. Key differences are noted, such as star connections providing a neutral point and being used for lower voltages, while delta connections having no neutral and being used for higher voltages. Formulas are presented relating line and phase voltages and currents for each connection type. Examples are worked through applying the formulas to calculate line voltage from phase voltage in a star-connected motor, and to calculate line current from phase current in a delta-connected motor.

2. TABLE OF CONTACT:
 Introduction
 Symbols of Star & Delta Connection
 Star & Delta Connection with power Supply
 Star & Delta Connection in Motor of 3 phase
 The difference between Star & Delta Connection .
 The Relationship between (I & V) in Star & Delta Connection
 Examples
 Quiz

3. INTRODUCTION:

4. SYMBOL OF STAR CONNECTION:
Symbol 1 Symbol 2

5. SYMBOL OF DELTA CONNECTION:
Delta Symbol

6. Δ Connection
power Source
Y Connection
Star & Delta connection with power source

7. Star
Delta
Connect Star & Delta connection in Motor of 3 phase

8. The difference between Star & Delta connection
Star Connection
1- Use for low
voltage
2- it give :
220 v , 380 v
3- There is a
Neutral or star
point
Delta Connection
1- Use for
High voltage
2- it give :
400v or more
3- No Neutral
point in delta
connection

9. The relationship and laws between I &V in Y & Δ
connection
Star Y SituationV line = V phase x
I line = I phase
Delta Δ Situation
V line = V phase
I line = I phase x

10. Table of laws between Voltage, Current,
in Star & Delta Connection
Name: Formula: Unit: Symbol:
Line Current (Y) IL = Iph Ampere A
Line Voltage (Y) VL = Vph x √3 Voltage V
Line Current (Δ) IL = Iph x √3 Ampere A
Line Voltage (Δ) VL = Vph Voltage V

11. EXAMPLE (1)
Q1 An electric motor has voltage phase = 220 V , Connected in Star .
A) Calculate the voltage in the line (Vline) ?

12. EXAMPLE (2)
Q2 An electric motor has Current phase = 70 A , Connected in Delta .
A) Calculate the current in the line (Iline) ?

13. THANK YOU FOR YOU
 Directed By:
 Mansour Ali AbuTalib
 Under Supervision Of The Teacher :
Mohammed elmaghawri