BASIC ELECTRO-MECHANICAL ENGINEERING
(EE-170)
Lecture#05
Engr. Ayla Safdar
Lecturer
Electrical Department
Example Circuit
Solve for the currents through each resistor
And the voltages across each resistor using
Series and parallel simplification.
Example Circuit
The 6 and 4 ohm resistors are in series, so
are combined into 6+4 = 10Ω
Example Circuit
The 8 and 10 ohm resistors are in parallel, so
are combined into 8∙10/(8+10) =14.4 Ω
Example Circuit
The 10 and 4.4 ohm resistors are in series, so
are combined into 10+4.4 = 14.4Ω
Example Circuit
+
I1∙14.4Ω
-
Writing KVL, I1∙14.4Ω – 50 v = 0
Or I1 = 50 v / 14.4Ω = 3.46 A
Example Circuit
+34.6 v -
+
15.4 v
-
If I1 = 3.46 A, then I1∙10 Ω = 34.6 v
So the voltage across the 8 Ω = 15.4 v
Example Circuit
+ 34.6 v -
+
15.4 v
-
If I2∙8 Ω = 15.4 v, then I2 = 15.4/8 = 1.93 A
By KCL, I1-I2-I3=0, so I3 = I1–I2 = 1.53 A
Three Phase Circuit
Objectives
Explain the differences between single-phase, two-
phase and three-phase.
Compute and define the Balanced Three-Phase
voltages.
Determine the phase and line voltages/currents for
Three-Phase systems.
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Wye and Delta Connections
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Delta Connection
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Delta Connected System
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Delta Connected System
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