Narration 1 00:00:01 --> 00:00:06 Hello everyone. Welcome to this tutorial on Steady State Response of Circuits. 2 00:00:07 --> 00:00:23 In this tutorial, we will study:

AC phase shift in RC, RL and LCR circuits.

Calculate Phase shift values and

Show circuit diagrams for our experiments.

3 00:00:24 --> 00:00:33 Here, I am using:

ExpEYES version 3.1.0

Ubuntu Linux OS version 14.10.

4 00:00:34 --> 00:00:49 To follow this tutorial, you should be familiar with:

Basic Physics and ExpEYES Junior interface. If not, for relevant tutorials in ExpEYES, please visit our website.

5 00:00:50 --> 00:00:54 Let's first define Steady state response of a circuit. 6 00:00:55 --> 00:01:01 Steady state response is a period of observance when a circuit is in equilibrium condition. 7 00:01:02 --> 00:01:09 Now, we will define phase shift. Phase shift is a relative change in the phase of a waveform. 8 00:01:10 --> 00:01:13 Let us now study AC phase shift in RC circuit. 9 00:01:14 --> 00:01:19 In this experiment, we will measure voltage variation and phase shift in the circuit. 10 00:01:20 --> 00:01:35 To perform this experiment,

A1 is connected to SINE. 1uF(one micro farad) capacitor is connected between SINE and A2. 1K resistor is connected between A2 and ground (GND).

11 00:01:36 --> 00:01:39 This is the circuit diagram. 12 00:01:40 --> 00:01:43 Let's see the result on the Plot window. 13 00:01:44 --> 00:01:53 On the Plot window, click on A1 and drag to CH1.

A1 is assigned to CH1.

14 00:01:54 --> 00:02:01 Click on A2 and drag to CH2.

A2 is assigned to CH2.

15 00:02:02 --> 00:02:07 Move the mSec/div slider to obtain the Sine waves. 16 00:02:08 --> 00:02:13 Click on EXPERIMENTS button. Select Study of AC circuits. 17 00:02:14 --> 00:02:23 Study of AC Circuits and Schematic windows open. Schematic window shows the circuit diagram. 18 00:02:24 --> 00:02:29 Study of AC Circuits window displays three traces with different voltages. 19 00:02:30 --> 00:02:34 Black trace is applied voltage at A1. 20 00:02:35 --> 00:02:38 Red trace is the voltage across the resistor. 21 00:02:39 --> 00:02:43 Blue trace is the voltage across the capacitor. 22 00:02:44 --> 00:02:48 On the right side of the window, we can see Phasor plot. 23 00:02:49 --> 00:02:55 On the plot, positive X-axis represents voltage across resistor. 24 00:02:56 --> 00:03:01 Positive Y-axis represents voltage across inductor. 25 00:03:02 --> 00:03:07 Negative Y-axis represents voltage across capacitor. 26 00:03:08 --> 00:03:33 Frequency of the waves is 149.4Hz.

Total voltage at A1 is 3.54V.

Voltage across R at A2 is 2.50V.

Voltage at A1-A2 is 2.43V.

Phase Shift is 43.1 deg(degree).

27 00:03:34 --> 00:03:43 Calculator shows default values of frequency, resistance, capacitance and inductance. 28 00:03:44 --> 00:03:52 Change the frequency value to 149.4Hz and Inductor value to 0 mH (zero milli henry). 29 00:03:53 --> 00:03:58 Click on Calculate XL, XC and Angle button. 30 00:03:59 --> 00:04:10 The values of XC, XL and phase angle are displayed. XC and XL are impedences of capacitance and inductance. 31 00:04:11 --> 00:04:19 Dphi is phase shift. Calculated Phase shift is 46.8 degrees. 32 00:04:20 --> 00:04:47 Let us calculate phase shift value using the formula: Φ (Phase shift) = arctan(XC/XR), where XC=1/2πfC.

Here f is frequency in hertz, C is capacitance in farads. Calculated value of phase shift is 46.81 deg.

33 00:04:48 --> 00:04:51 Now, we will study AC phase shift in RL circuit. 34 00:04:52 --> 00:04:58 In this experiment, we will measure phase shift when capacitor is replaced by an inductor. 35 00:04:59 --> 00:05:10 To perform this experiment, A1 is connected to SINE.

A 3000 turns coil is connected between SINE and A2.

36 00:05:11 --> 00:05:19 560 Ohm resistor is connected between A2 and GND. This is the circuit diagram. 37 00:05:20 --> 00:05:23 Let's see the result on the Plot window. 38 00:05:24 --> 00:05:26 Two sine waves are generated. 39 00:05:27 --> 00:05:37 Click on EXPERIMENTS button, select Study of AC circuits. Study of AC Circuits window opens. 40 00:05:38 --> 00:05:42 On the right side of the window, we can see Phasor plot. 41 00:05:43 --> 00:05:52 You can see that Phase Shift is -2.7 deg (minus 2.7 degree). Notice the values of frequency and voltages. 42 00:05:53 --> 00:06:10 Change the value of:

Frequency to 149.4Hz(hertz)

Resistance to 1360 Ohm

Capactance to 0 uF(micro farad) and

inductance to 78 mH (milli henry).

43 00:06:11 --> 00:06:22 Click on Calculate XL, XC and Angle button to view the values. Calculated phase shift is -3.1 deg(minus 3.1 degree). 44 00:06:23 --> 00:06:26 Let us calculate phase shift value using the formula. 45 00:06:27 --> 00:06:40 Phase shift (Φ) = arctan(XL/XR), where XL=2πfL. Here L is inductance. 46 00:06:41 --> 00:07:04 External resistance value is 560 Ohm and resistance of the coil is 800 Ohm. Total resistance =( 560 Ohm + 800 Ohm)= 1360 Ohm.

Calculated value of the phase shift is 3.08degrees.

47 00:07:05 --> 00:07:09 Now, we will study AC phase shift in LCR circuit. 48 00:07:10 --> 00:07:16 We will measure phase shift when inductor & capacitor are connected in the circuit. 49 00:07:17 --> 00:07:20 To perform this experiment, SINE is connected to A1. 50 00:07:21 --> 00:07:27 Coil and 1 uF(1 micro farad) capacitor are connected between A1 and A2. 51 00:07:28 --> 00:07:35 1K resistor is connected between A2 and ground (GND). This is the circuit diagram. 52 00:07:36 --> 00:07:38 Let's see the result on the Plot window. 53 00:07:39 --> 00:07:42 Two sine waves are generated with a phase shift. 54 00:07:43 --> 00:07:49 Click on EXPERIMENTS button, select Study of AC Circuits. 55 00:07:50 --> 00:07:58 Study of AC Circuits and Schematic windows open. Schematic window shows the circuit diagram. 56 00:07:59 --> 00:08:05 Study of AC Circuits window displays three sine waves with different voltages. 57 00:08:06 --> 00:08:10 On right side of the window, we can see Phasor plot. 58 00:08:11 --> 00:08:32 Frequency of the waves is 149.4Hz,

Total voltage at A1 is 3.53V, Voltage across R at A2 is 2.50V, Voltage of LC across A1-A2 is 2.42V.

59 00:08:33 --> 00:08:36 Phase Shift is 43.1 deg(degree). 60 00:08:37 --> 00:08:47 Change the value of:

frequency to 149.4Hz and

inductance to 78mH (milli Henry).

61 00:08:48 --> 00:08:59 Click on Calculate XL, XC and Angle button to view the values. Calculated phase shift value is 44.8 deg. 62 00:09:00 --> 00:09:03 Let us calculate Phase shift value using the formula. 63 00:09:04 --> 00:09:09 Phase shift Φ = arctan(XC – XL/XR). 64 00:09:10 --> 00:09:19 External resistance value is 1000 Ohm. Calculated value of the phase shift is 44.77 degrees. 65 00:09:20 --> 00:09:21 Let us summarize. 66 00:09:22 --> 00:09:32 In this tutorial, we have studied-

AC phase shift in RC, RL and LCR circuits and Calculated the phase shift values.

67 00:09:33 --> 00:09:43 As an assignment,

study AC Phase shift of RL and LCR circuits, using different resistance & capacitance values.

68 00:09:44 --> 00:09:51 This video summarizes the Spoken Tutorial project. If you do not have good bandwidth, you can download and watch it. 69 00:09:52 --> 00:09:58 We conduct workshops using Spoken Tutorials and give certificates. Please contact us. 70 00:09:59 --> 00:10:05 The Spoken Tutorial Project is funded by NMEICT, MHRD, Government of India. 71 00:10:06 --> 00:10:11 This tutorial is contributed by Kaushik Datta and Madhuri Ganapathi.Thank you for joining.