CALIFORNIA STATE UNIVERSITY, FULLERTON DEPARTMENT OF ELECTRICAL ENGINEERING EG-EE 203L Experiment 4 CIRCUIT ANALYSIS AND THEOREMS I. BACKGROUND The purpose of this experiment is to allow the student to experimentally verify certain circuit analysis techniques and circuit theorems that have been discussed theoretically, in EG-EE 203. In order to do this you will make use of the circuit shown in Fig. 1. -Vs.+ ww Rs www R3 Az' Iz E + V4 www Z x' x -V2+ www R2 FIG. 1 The circuit contains four pairs of terminals w-w', x-x', y-y', and z-z'. As shown in Figure 1, the terminals of each of these pairs are shorted together with a short link. Any link may be removed, and either a voltage source or a milliammeter may be inserted in its place. Every time a voltage source is inserted, let its positive terminal be connected to terminal w, x, y, or z and its negative terminal to terminal w', x', y' or z'. In order to do the experiment you will need sources of 5 VDC and 10 VDC. You will be expected to set up your PS 503A power supply to serve for both sources. Except where otherwise stated you will be expected to use the DM502 to make the voltage measurements required. (Read the equipment notes on the DM502 digital multimeter). The Simpson multimeter may be used to measure currents. 47 II. PREPARATION A. Let R2=2 KQ, R3= 3 K2, R4=4 K, and R5= 5 KQ. 1. Assume that the 10V source is inserted at x-x'. Predict the values of V2 and V3. 2. Assume instead that the 5V source is inserted at y-y'. Predict the values of V2 and V3. 3. Assume that the 10V source is inserted at x-x' and the 5V source is inserted at z-z'. Predict Iy and V2. 4. Assume that the 5V source is inserted at x-x'. Predict the values of Iz. 5. Assume that the 10V source is inserted at x-x' and the 5V source is inserted at y-y'. Using superposition and the results obtained in parts II.A.1 and II.A.2 predict the values of V2 and V3. 500 KQ B. Let R2=200 KS2, R3= 300 K2, R4= 400 KS, and R5= 500 KN. 1. Assume that the 10V source is inserted at w-w' and the 5V source is inserted at y-y'. Predict the values of V2 and V5. C. Calculate the Thévenin equivalent of all the circuit of Part II.A.3 except R2. egalov a ro gefiov a smit III. IN THE LABORATORY A. Set up the circuit of Fig. 1 with the values given in Part II.A. In each of the following steps find the percent difference between the experimental and predicted values. 1. Verify the predictions made in Part II.A.1. 2. Verify the predictions made in Part II.A.2. 48 3. Test the superposition theorem by inserting both the 10V source at x-x' and the 5V source at y-y'. Measure V2 and V3 and verify the predictions made in part II.A.5. 4. Verify the predictions made in Part II.A.3. 5. Verify the prediction made in part II.A.4. Insert milliammeter at z-z' 6. The Reciprocity theorem says that, in a bilateral network if you interchange the positions of the voltage source and the milliammeter, the milliammeter reading will be unchanged. Make this change in the circuit of Part II.A.4. and verify the theorem. B. Set up the circuit of Fig. 1 with the values given in Part II.B. 1. Measure V2 first with the DM502 and then with the Simpson multimeter. Compare your measurements with the prediction made in Part II.B.1. Summarize the results in the following table and explain the results. Note: For DM502, RM=10MQ TDS For Simpson RM=20KQ/VDC. To find RM, 20K has to be multiplied by the voltage scale being used. Table for V2 large time com Calculated II.B.1 DM 502 Simpson 260 The Amy 2. Measure V5 first with the DM502 and then with the Simpson multimeter. Compare your measurement with the prediction made in Part II.B.1. Do these results compare in a manner similar to what was found in Part III.B.1? Summarize the results in the following table and explain the results. Table for V5 Calculated II.B.1 DM 502 Simpson 260 49 C. Set up the circuit shown in Fig. 2 using the values calculated in Part II.C. Measure V2 and compare with the value obtained in Part III.A.4. RTH www Voc FIG. 2 + R2 = 2K D. What conclusions do you draw from this experiment? R-300 Predic EV 50