Download Inductor Energizing - Laboratory Experiment 4 | TEET 3145 and more Lab Reports Electrical Circuit Analysis in PDF only on Docsity! Circuit Analysis II TEET 3145 Laboratory # 4 Inductor Energizing Fall 2009 Georgia Southern University Mechanical and Electrical Engineering Technology Page 1 of 5 Name: ________________________ Your Partner Name: ________________________ Introduction: According to the theory presented in lecture and the text, an inductor energizes and de- energizes exponentially with a time constant of R L =τ . Here L is the total inductance and R is the total resistance of the circuit. If inductors are connected in series, it is like adding more turns to a single inductor. The combination is the sum of the individual inductances. When inductors are connected in parallel, the total inductance appears less since the current, producing the magnetic flux, is split. Similar to resistors, inductors in parallel combine for a total inductance of 21 11 1 LL LT + = . This parallel inductor calculation can only be done for ideal inductors. Ideal inductors have zero internal resistance. Procedure: 1. Before building the circuit shown in fig. 1, measure and record the actual value of the inductor and resistor that will be used in this experiment. Use the inductance- capacitance-resistance (LCR) meter that is available in the lab. Nominal values: L = 15 mH, R1 = 560 Ω Measured values: L = ___________ R1 = _____________ You will use the measured values for the calculations. 2. Use an ohmmeter to measure the resistance of the wire making up the coil of the inductor. RL = ______________ 3. Note the function generator’s output resistance (look at the generator front panel, by the output connector). This is part of the series resistance when calculating the time constant. Rgen = __________________ Circuit Analysis II TEET 3145 Laboratory # 4 Inductor Energizing Fall 2009 Georgia Southern University Mechanical and Electrical Engineering Technology Page 2 of 5 4. Calculate the time constant. Use RT = R1 + RL + Rgen ; RT = ______________ τ = _______________ 5. A good practice is to make sure the voltage source (the function generator) is properly set up before connecting the circuit. Connect the function generator directly to the oscilloscope channel 1. 6. Set the function generator frequency such that the period is ten time constants (T = 10 τ ). Set the function generator voltage to Vs = 2.0 Vp-p square wave. Use the offset control in the signal generator so that the voltage ranges from 0 to +2v. T =________________ ; f = _________________________ 7. Build the RL series circuit shown in fig. 1 Fig. 1. RL series circuit 8. Measure the voltage across the inductor using channel 2 of the oscilloscope. (Commonly this will cause some distortion of the input signal.) 9. Adjust the oscilloscope so that the function generator voltage appears in the top half of the display, while the inductor voltage appears in the bottom half of the display. 10. Sketch below the signals displayed on the oscilloscope. Indicate volts/div and sec/div
