expt no 4 delta-wye
TRANSCRIPT
EXPERIMENT No. 4
DELTA – WYE TRANSFORMATION OF RESISTANCE NETWORK
OBJECTIVES:
1. To verify experimentally the principle of delta-wye and wye-delta transformation.
2. To prove that the delta networks can be transformed into its equivalent Wye or delta network.
3. To learn to connect a circuit.
INTRODUCTORY INFORMATION:
Situations open arise in circuit analysis when the resistors are neither in parallel nor in series. Many circuits of the type can be simplified by using three terminal equivalent networks. These networks are the Wye (Y) or Tee (T) (see figure 4.1 a) and the Delta (∆) or Pi ( ) (figure 4.1 b). These networks occur by themselves or as part ofπ larger network. They are used in three-phase networks, electrical filters and matching networks.
Figure 4.1 (a) Wye or Tee Network
Figure 4.1 (b) Delta or Pi Network
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NETWORK CONVERSION
Figure 4.2DELTA TO WYE CONVERSION
Suppose it is more convenient to work with a Wye network in a place were the circuit contains a delta configuration. To obtain the equivalent resistances in the Wye network, we compare the two networks and make sure that the resistance between each pair of nodes in the delta network is the same as the resistance between the same pair of nodes in the Wye network.
To transform a Delta Network to Wye Network, consider figure 4.2, we create an extra node n and follow this:
Each resistor in the Wye Network or Tee Network is that product of the resistors in the two adjacent Delta branches, divided by the sum of the three Delta resistors.
WYE TO DELTA CONVERSION
Suppose it is more convenient to work with a Delta Network in a place where the circuit contains a Wye configuration. To obtain the equivalent resistances in the Delta Network, we compare the two networks and make sure that the resistance between each pair of nodes in the Wye network is the same pair of nodes in the Delta network.
The conversion formulas for transforming a Wye network to an equivalent Delta network:
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The conversion rule for wye to delta is each resistor in the Delta Network is the sum of all possible products of Wye resistors taken two at a time, divided by the opposite Wye resistor.
The Wye and Delta Networks are said balanced when: or .
Under this condition, conversion formula become:
MATERIALS REQUIRED:
1 pc. Circuit Board 1 pc. Digital Multimeter 1 pc. Analog Multimeter 1 unit DC Power Supply Connecting Wires Resistors: 3 pcs. 1000 Delta NetworkΩ 3 pcs. 3000 Wye NetworkΩ
PROCEDURE:
1. Connect the circuit as shown in Fig. 4-a. (use 3 – 1000 ohms for that circuit.
2. Turn – ON the power supply3. Measure the voltage drop across and the current . 4. Record the measured quantity on table 4.1.5. Connect the circuit as shown in fig. 4-b. (use 3 -3000 ohms for that
circuit)6. Turn – ON the power supply7. Measure the voltage drop across and the current . 8. Record the measured quantity on table 4.29. Compare the data recorded form table 4.1 and 4.2.10. Formulate relationship between wye and delta network.
SCHEMATIC DIAGRAM:
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Figure 4-a Figure 4-b
TABLE 5.1
Delta Network
Measured Value Computed ValuePercent Difference
TABLE 5.2
Wye Network
Measured Value Computed ValuePercent Difference
Note: Include the unit.
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COMPUTATION
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DRAWINGS/SET-UP
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OBSERVATION AND ANALYSIS
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CONCLUSION
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QUESTIONS:
1. Transform the given circuit to its equivalent Wye circuit.
2. Transform the given circuit t its equivalent Delta circuit.
ANSWERS
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