Lab Experiment No. 2 Resistor Connections

I. IntroductionIn this lab exercise, you will learn –• how to read schematic diagrams of electronic networks,• how to transform schematics into actual element connections,• correct ways to layout a breadboard connection of a network,• how to connect the DMM for measuring resistance, and• how to combine resistors to establish terminal equivalence.

II. Experiment ProcedureA collection of resistive networks are given in Figures 1 through 6. The schematic diagram of the network is shown in (a) while the resistor connection is shown in (b) in each Figure. Obtain from the lab GTA all of the resistors required for these experiments. Use these resistors to correctly layout each of these networks on your breadboard. Apply the bench DMM to take measurements and make calculations required to fill out the tables provided with each network. Use specified and calculated values as the basis for percentage variations.

(a) Series connection. A series connection of resistors is shown in Figure 1. The schematic diagram of this connection is shown in Figure 1(a) while the actual resistor connection is shown in Figure 1(b). Fill out Table 1 with data obtained below.

i. Measure the resistance of each resistor in the series connection.ii. With the specified resistor value as the basis, calculate resistor variations in per-cent (%).iii. Calculate the value of the resistance at the terminals A-B. This is the terminal resistance RAB.iv. Apply the DMM to measure RAB.v. Calculate the variation in RAB in (%).

(b) Parallel connection. A parallel connection of resistors is shown in Figure 2. The schematic diagram of this connection is shown in Figure 2(a) while actual resistor connection is shown in Figure 2(b). Fill out Table 2 with data obtained below.

i. Measure the resistance of each resistor in the parallel connection.ii. With the specified resistor value as the basis, calculate resistor variations in per-cent (%).iii. Calculate the value of the resistance at the terminals A-B. This is the terminal resistance RAB.iv. Apply the DMM to measure RAB.v. Calculate the variation in RAB in (%).

(c) Series/parallel combination. A series connection of parallel resistors is shown in Figure 3. The schematic diagram of this connection is shown in Figure 3(a) while the actual resistor connection is shown in Figure 3(b). Fill out Table 3 with data obtained below.

i. Measure the resistance of each resistor in the connection.ii. With the specified resistor value as the basis, calculate resistor variations in per-cent (%).iii. Calculate the value of the resistor Rx that will produce a terminal resistance RAB of 84Ω.iv. Obtain this resistor from the lab GTA and connect it into the network.v. Apply the DMM to measure RAB.vi. Calculate the variation in RAB from 84Ω in (%).

(d) Parallel/series combination. A parallel connection of series resistors is shown in Figure 4. The schematic diagram of this connection is shown in Figure 4(a) while the actual resistor connection is shown in Figure 4(b). Fill out Table 4 with data obtained below.

i. Measure the resistance of each resistor in the connection.ii. With the specified resistor value as the basis, calculate resistor variations in per-cent (%).iii. Calculate the value of the resistor Rx that will produce a terminal resistance RAB of 1.83KΩ.iv. Obtain this resistor from the lab GTA and connect it into the network.v. Apply the DMM to measure RAB.vi. Calculate the variation in RAB from 1.42KΩ in (%).

(e) Combination 1 (Combo 1) connection. A combination connection of resistors in series and parallel is shown in Figure 5. The schematic diagram of this connection is shown in Figure 5(a) while the actual resistor connection is shown in Figures 5(b). Fill out Table 5 with data obtained below.

i. Measure the resistance of each resistor in the connection.ii. With the specified resistor value as the basis, calculate the resistor variation in per-cent (%).iii. Calculate the value of the resistance at the terminals A-B. This is the terminal resistance RAB.iv. Apply the DMM to measure RAB.v. Calculate the variation in RAB in (%).

(f) Combination 2 (Combo 2) connection. Yet another combination connection of resistors in series and parallel is shown in Figure 6. The schematic diagram of this connection is shown in Figure 6(a) while the actual resistor connection is shown in Figures 6(b). Fill out Table 6 with data obtained below.

i. Measure the resistance of each resistor in the connection.ii. With the specified resistor value as the basis, calculate the resistor variation in per-cent (%).iii. Calculate the value of the resistance at the terminals A-B. This is the terminal resistance RAB.iv. Apply the DMM to measure RAB.v. Calculate the variation in RAB in (%).

III. Lab ReportThe report for this lab experiment must be word-processed and contain the following items –• Title Page.• Introduction.• Procedure.• Results.• Discussions.

(a) Suggest useful applications for the connections studied in this experiment.• Conclusion. Provide detailed comments and discussions on the items listed below for each resistor network.

(a) Are all resistors within tolerance? List those that are not.(b) Account for the difference between measured RAB and calculated RAB (that is, the calculated variation or

tolerance of RAB).(c) Explain how the variation in RAB corresponds to resistor tolerance.(d) Explain how close the calculated values of Rx in the series/parallel and parallel/series connections are to

standard resistor values. Consider resistor tolerance.• Appendix.• References.

Series Connection

Figure 1(a) Schematic for the series connection

(b) Component connection diagram

Table 1Series connection

Resistor(Ri)

Specified value(Ω)

Measured value(Ω)

Variation(%)

R1 3.9K

R2 2K

R3 5.1K

R4 1.2K

R5 8.2K

Terminalresistance

Calculated value(Ω)

Measured value(Ω)

Variation(%)

RAB

Parallel Connection

Figure 2(a) Schematic for the parallel connection

(b) Component connection diagram

Table 2Parallel connection

Resistor(Ri)

Specified value(Ω)

Measured value(Ω)

Variation(%)

R1 10K

R2 7.5K

R3 15K

R4 3.3K

R5 2.2K

Terminalresistance

Calculated value(Ω)

Measured value(Ω)

Variation(%)

RAB

Series/Parallel Connection

Figure 3(a) Schematic for the series/parallel connection

(b) Component connection diagram

Table 3Series/parallel connection

Resistor(Ri)

Specified value(Ω)

Measured value(Ω)

Variation(%)

R1 15

R2 12

R3 30

R4 27

R5 56

R6 75

R7 62

R8 82

R9 91

Rx

Terminalresistance

Specified value(Ω)

Measured value(Ω)

Variation(%)

RAB 84

Parallel/Series Connection

Figure 4(a) Schematic for the parallel/series connection

(b) Component connection diagram

Table 4Parallel/series connection

Resistor(Ri)

Specified value(Ω)

Measured value(Ω)

Variation(%)

R1 1.5K

R2 1.2K

R3 3K

R4 2.7K

R5 5.6K

R6 7.5K

R7 6.2K

R8 8.2K

R9 9.1K

Rx

Terminalresistance

Specified value(Ω)

Measured value(Ω)

Variation(%)

RAB 1.83K

Combo 1 Connection

Figure 5(a) Schematic for Combo 1 connection

(b) Component connection diagram

Table 5Combo 1 connection

Resistor(Ri)

Specified value(Ω)

Measured value(Ω)

Variation(%)

R1 200

R2 1.3K

R3 3.6K

R4 1.2K

R5 1.8K

R6 1.3K

R7 2.2K

R8 2.2K

R9 1.2K

R10 300

R11 1K

R12 1.5K

R13 3K

R14 1K

R15 2K

R16 1K

Terminalresistance

Calculated value(Ω)

Measured value(Ω)

Variation(%)

RAB

Combo 2 connection

Figure 6(a) Schematic for Combo 2 connection

(b) Component connection diagram

Table 6Combo 2 connection

Resistor(Ri)

Specified value(Ω)

Measured value(Ω)

Variation(%)

R1 47K

R2 30K

R3 120K

R4 20K

R5 30K

R6 15K

R7 30K

R8 22K

R9 10K

R10 300K

R11 100K

R12 15K

R13 100K

R14 150K

R15 15K

R16 75K

Terminalresistance

Calculated value(Ω)

Measured value(Ω)

Variation(%)

RAB