Fakulti: FACULTY OF BIOSCIENCES AND MEDICAL ENGINEERING Semakan Nama Matapelajaran: Laboratory 1 Tarikh Keluaran Kod Matapelajaran : SMBE 2712 Pindaan Terakhir No. Prosedur : : 2013 : 2017 : FACULTY OF BIOSCIENCES AND MEDICAL ENGINEERING UNIVERSITI TEKNOLOGI MALAYSIA SMBE 2712 LABORATORY 1 STUDENT PACK CIRCUIT THEORY Disediakan oleh Disahkan oleh Nama : Arief Ruhullah bin A Harris Nama : Tandatangan : Tandatangan : Cop : Cop : Tarikh : 10/9/2017 Tarikh :
Introduction This laboratory consists of three sessions that requires the students to study, calculate and implement some basic circuits theory. In the first session, students are required to study, calculate and implement R-L and R-C series transient circuits. For the second session, students will be exposed with two-port network circuit. The final session, students will implement Thevenin and Norton Theorem circuits. Experiment 1 (week 1): R-L and R-C Series Transient circuits Objective To study, calculate and implement R-L and R-C series transient circuits. Equipments 1. RF Electronics Training system (Circuit Theory 3) 2. Adapter 3. Connection Wires (banana plug) 4. Multimeter x 2 5. Oscilloscope Pre-lab (Must be done before the lab session) 1. Explain the time constant, τ in circuit analysis 2. For the circuit in Figure 1a below, a. Derive an expression of V R (t) = V s (t)e -(t/τ) ) and V R (t) =V s (1-e -(t/τ) ) where τ=l/r b. If R= 4 kω, 6 kω, 8 kω, L= 100mH and Vs=5V (step response or square wave with 1kHz): i. Determine V R (t) and V R (t) at t = τ, 2τ, 3τ for the mentioned values of R. 2
ii. Sketch the response of V R (t) and V R (t) versus t iii. Calculate the theoretical instantaneous current i(t) values for t = τ, 2τ, 3τ. 3. For the circuit in Figure 1b below, a. Derive an expression of V c (t) = V s (t)e -(t/τ) ) and V c (t) =V s (1-e -(t/τ) ) where τ=rc b. If C= 0.05μF, 0.10μF, 0.15μF, R= 1 kω and Vs=5V (step response or square wave with 1kHz): i. Determine V c (t) and V c (t) at t = τ, 2τ, 3τ for the mentioned values of C. 3
ii. Sketch the response of V c (t) and V c (t) versus t iii. Calculate the theoretical instantaneous current i(t) values for t = τ, 2τ, 3τ. Lecturer approval: Stamp: Figure 1a Figure 1b Tasks 1. Based on the steps in the pre-lab exercise, construct the RL circuit as in Figure 1a. 2. Record your results and compare with your pre-lab exercise. Use cursor function on oscilloscope to obtain Δt (time difference) and ΔV (voltage difference). 3. Construct the RC circuit as in Figure 1b with the same values as in pre-lab exercise. 4. Record your results and compare with your pre-lab exercise. Use cursor function on oscilloscope to obtain Δt and ΔV. Refer page 6 for oscilloscope cursor function manual. 5. Discuss and make comparison between the result of experiment and theory. 4
Results: RL Theory (calculation) Experiment 4 kω 6 kω 8 kω 4 kω 6 kω 8 kω V R (t) Δt ΔV Δt ΔV Δt ΔV Δt ΔV Δt ΔV Δt ΔV τ 2τ 3τ V R (t) Δt ΔV Δt ΔV Δt ΔV Δt ΔV Δt ΔV Δt ΔV τ 2τ 3τ RC Theory (calculation) Experiment 0.05μF 0.10μF 0.15μF 0.05μF 0.10μF 0.15μF V c (t) Δt ΔV Δt ΔV Δt ΔV Δt ΔV Δt ΔV Δt ΔV τ 2τ 3τ V C (t) Δt ΔV Δt ΔV Δt ΔV Δt ΔV Δt ΔV Δt ΔV τ 2τ 3τ Discussion: Conclusion: Lecturer approval: Stamp: 5
How to use cursor function in Oscilloscope A B C D1/D2 E F 1. Push the cursor button (B) 2. Set the cursor type to TIME by pushing button E 3. Select cursor 1 by pushing button D1 4. Adjust the cursor 1 to desired duration start (e.g beginning of rise time) using dial A 5. Select cursor 2 by pushing button D2 6. Adjust the cursor 2 to desired duration end (e.g desired t on C) using dial A. 7. Refine the duration by adjusting the time resolution with button F and adjust again the cursors. 8. Read and record the v on C. 6
Experiment 2 (week 2): Two-port Network Objective To analyze T and π network into ABCD parameters and z parameters. Equipments 1. DC power supply 2. Multimeter x 2 3. Connection wires (jumpers) 4. Proto board 5. 27 Ω (1 watt) resistors x 3 6. 51 Ω (1 watt) resistors x 3 7. 30 Ω (1 watt) resistors x 3 Pre-lab (Must be done before the lab session) 1. Write down the formula to convert a T network to its equivalent π network. 2. Calculate Z parameters from Figure 2 Where Z 1 = Z 2 = Z 3 =27Ω and V 1 =5V. 3. Sketch and calculate the equivalent π network circuit. Lecturer approval: Stamp: 7
Figure 2 Tasks 1. Construct the T network circuit as in Figure 2 with Z 1 = Z 2 = Z 3 =27Ω and V 1 =5V 2. Keep output port open circuited i.e. I 2 =0. Measure the current I 1 by connecting multimeter in series with Z 1. 3. Measure voltage V 2 by multimeter. 4. Obtain Z parameters of the T network. 5. Keep input port open circuited i.e. I 1 =0. Measure the current I 2 by connecting multimeter in series with Z 2. 6. Observe and discuss the values of the parameters. 7. Construct the equivalent π network circuit and repeat step 2-6. 8
Results: I 2 =0 I 1 =0 Calculation Experiment (T network) Experiment (π network) Calculation Experiment (T network) V 1 =5V V 2 =5V V 2 = V 1 = I 1 = I 2 = Z 11 = Z 12 = Z 21 = Z 22 = Experiment (π network) Discussion: Conclusion: Lecturer approval: Stamp: 9
Experiment 3 (week 3): Thevenin and Norton Theorem Objective To obtain Thevenin and Norton equivalent circuit from a complex circuit Equipments 1. DC power supply 2. Multimeter x 2 3. Connection wires 4. Proto board 5. Resistors 10Ω x 2, 12Ω, 20Ω, 30Ω, 50Ω, 100Ω x 2, 150Ω, 200Ω 6. Variable resistor 1kΩ x2. Pre-lab (Must be done before the lab session) 1. Explain what is the function of Thevenin and Norton Theorem. 2. Calculate the Thevenin equivalent resistance R Th of Figure 3a below with open circuit at terminal A-B. 3. Calculate the Thevenin voltage V Th of figure 3a (Open circuit voltage at terminal A-B) and Norton current I N (Short circuit current at terminal A-B without R L ). Lecturer approval: Stamp: 10
1V Tasks Figure 3a 1. Construct the circuit as in Figure 3a. 2. Measure and record the ammeter readings I L for load resistance, R L =0 Ω, 10 Ω, 20 Ω, 30 Ω, 50 Ω, 100 Ω, and 200 Ω. 3. Record your results. 4. From figure 3a, open the terminal a-b (Remove R L ), measure the Thevenin voltage V Th (Open circuit voltage at terminal A-B) and Norton current I N (Short circuit current at terminal A-B). 5. Replace the 1V voltage supply with a wire (short circuit) and measure the Thevenin equivalent resistance R Th at terminal A-B. 6. Construct a Thevenin equivalent circuit as in Figure 3b using measured value of R Th and V Th. 7. Repeat step 2 and 3. 8. Construct a Norton equivalent circuit as in Figure 3c using measured value of R N = R Th and adjust the Supply voltage E to get the value of I N equals to the measured value in step 5. 9. Repeat step 2 and 3. Figure 3b Figure 3c 11
Results: R Th V Th I N Calculation Experiment R L I L I L (Thevenin) I L (Norton) E 0 Ω 10 Ω 20 Ω 30 Ω 50 Ω 100 Ω 200 Ω Discussion: Conclusion: Lecturer approval: Stamp: 12