Electric Circuit II Lab Manual Session #1

Transcription

1 Department of Electrical Engineering Electric Circuit II Lab Manual Session #1 Subject Lecturer Dr. Yasser Hegazy Name: Group:

2 Lab Policies 1. Each lab session lasts 90 min and starts promptly. A brief introduction with demo may be given by the instructor at the beginning of the lab. Everybody has to finish on time, so please time yourself carefully. Doing the pre-lab can save you a lot of time. 2. Preparing the lab is very important; as it will save you time and allow you to work more efficiently. The pre-lab includes reading the lab assignment in advance, answering the questions or doing the calculations, and if necessary reviewing the material in the textbook. All pre-lab preparation must be recorded and dated in the lab notebook prior do doing the lab. The lab instructor will check your pre-lab write-up and sign your notebook. 3. As a part of the lab preparation, you can use Spice to simulate the actual experiments you will be doing in the lab. Spice is available in the PC labs. You can paste the result of the simulations in the notebook. Make sure you label the graphs and tables clearly. If you make the simulation prior to the lab you must bring the print out of the simulated results. 4. Pre-lab Quiz, Each week there is an Oral quiz. This quiz must be taken at the beginning of your lab session. 5. Student partnerships, Each lab is done in groups of two. The team approach encourages interaction and helps with the debugging and data collection. Each student has his/her own lab notebook and is responsible for recording the pre-lab, recording the measurement data. However, lab report has to be handed in individually. 6. Collaboration, Students are working in groups of two in the laboratory. This encourages team work and makes the conduction of the experiments more efficient. You can collaborate on the pre-lab and on interpretation of the measured data. However, each student is responsible for writing the pre-lab and recording the data in his or her notebook. Copying of data from other groups or altered information will result in a zero grade. The lab report is a joined effort and each student should contribute equally to writing the report. 7. Each lab notebook needs to be signed and dated by the instructor or TA before leaving the lab. The instructor will check the pre-lab and notebook entries for the current lab assignment. The students are responsible for securing the signature. 8. Instruments and supplies, The major instruments you will need are permanently installed in the stations. A selection of wires, cables and connectors are inside your kit. Small parts (resistors, capacitors, transistors, ICs) will be available in the bins in the lab area. Capacitors, transistors and integrated circuits (ICs) can be reused and should be left on the table in the same manner as they were obtained. 2

3 9. Leave your workplace at least as clean and tidy as you found it. Put everything back in its proper place. If the workplace is not tidy after you finish it will cause to lose some Marks. Please be sure to Close your PC after you finish of simulations. 10. Grading Policy The lab is 20 Marks divided into 12 for reports & 8 for pre lab quiz. 11. Lab Report and Turn-In Policy The lab report due date is the following lab. Note : No Late Reports are accepted 12. Precautions Electronic test equipment can be damaged if incorrectly used. The function generator will be damaged if a large DC or AC voltage is applied to the outputs. The oscilloscope also has input limitations. Do not exceed 300V on any oscilloscope input. Power supplies can also be damaged if an external voltage in excess of the supply output voltage is fed back into the supply. The most common ways multi-meters are damaged are by trying to measure voltage when the meter is set to measure current or resistance or by exceeding the maximum voltage when in the voltage measurement mode. Think twice before connecting a meter. In particular, check the position of the function switch and ensure the test leads are connected to the proper inputs on the meter. If you make a mistake you could blow the meter s internal fuse or damage the converter chip. Our lab procedures are designed to avoid these problems but you should always be aware of your test equipment s limitations.no foods or drinks are allowed inside the lab for any reason. 13. Material the sessions are uploaded weekly on your Site eee.guc.edu.eg.for Pspice, there is a good tutorial for Pennsylvania University Department of Electrical and Systems Engineering in this link Project there will be a project at the end of the lab sessions to examine your gain knowledge in the lab. Acknowledgement to Eng.Mohamed El Hadidy as his material helped us in preparing these labs. 3

4 Oscilloscope Front Panel 4

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6 CRT: (6) POWER Main power switch of the instrument. Turn on the switch to get the LED (5) lighted. (2).INTEN Control the brightness of the spot or trace. (3) FOCUS Focus the trace to the sharpest image. (4) TRACE ROTATION Semi-fix potentiometer for aligning the horizontal trace in parallel with graticule lines. (33) FILTER The filter is easy for waveform viewing. Vertical Axis: (8) CH1 (X) input The vertical input terminal of CH1 is X-axis in X-Y operation. (20) CH 2 (Y) input The vertical input terminal of CH2 is Y-axis in X-Y operation. (10) & (18) AC-GND-DC Select connection mode between input signal and vertical amplifier. AC AC coupling GND Vertical amplifier input is grounded and input terminals are disconnected. DC DC coupling (7) & (22) VOLTS/DIV Select the vertical axis sensitivity from 5mV/DIV to 5V/DIV with 10 ranges totally. (9) & (21) VARIABLE Fine adjustment of sensitivity with a factor of _1/2.5 of the indicated value. The sensitivity is calibrated to specific value in the CAL position. When this knob is pulled out (x5 MAG state), it will multiply 5 by the amplifier sensitivity. (13) & (17) CH1 & CH2 DC BAL. The knobs are used for adjusting the attenuator balance. See DC BAL adjustments for details. 6

7 (11) & (19)56POSITION Vertical positioning control of trace or spot. (14)VERT MODE: Select operation modes of CH1 and CH2 amplifiers. CH1 Operate the oscilloscope as a single-channel instrument by selecting CH1 alone. CH2 Operate the oscilloscope as a single-channel instrument by selecting CH2 alone. DUAL Operate the oscilloscope as a dual-channel instrument by selecting CH1 and CH2. ADD The oscilloscope displays the algebraic sum (CH1 + CH2) or subtraction (CH1 - CH2). (The subtraction function effects only when push in CH2 INV (16) button). When this switch is released in the dual-trace mode, the channel 1 and channel 2 inputs are alternately displayed (Normally used at faster sweep speeds). When this switch is depressed in the dual-trace mode, the channel 1 and channel 2 inputs are chopped and displayed simultaneously. (Normally used at slower sweep speeds). (16)CH2 INV When press CH2 INV button, it will inverts the CH2 input signal in CH2 and in ADD MODE, the channel 2 trigger signal pickoff is also inverted. Triggering (24) EXT TRIG IN input terminal Input terminal is used for external triggering signal. To use this terminal, set SOURCE (23) to the EXT position. (23) SOURCE Select the internal triggering source signal, and the EXT TRIG IN input signal. CH1 Press key DUAL or ADD of VERT MODE (14), select CH1 to get internal triggering source signal. CH2 Press key DUAL or ADD of VERT MODE (14), select CH2 to get internal triggering source signal. (27) TRIG.ALT Set VERT MODE switch (14) in DUAL or ADD key, select CH1 or CH2 by the SOURCE switch (23), then press TRIG.ALT switch (27), the internal triggering source signal will display alternately from CH1 and CH2. 7

8 LINE Display the triggering signal from AC power line frequency signal. EXT Obtain the external triggering source signal by applying external signal to EXT TRIG IN input terminal (24). (26) SLOPE Triggering slope button. + Triggering occurs when the trigger signal crosses the trigger level by positive-going course. - Triggering occurs when the trigger signal crosses the trigger level by negative-going course. (28) LEVEL Display a synchronized stationary waveform and set a start point for the waveform. Toward + The trigger level moves upward on the display waveform. Toward - The trigger level moves downward on the display waveform. (25) TRIGGER MODE Trigger mode selection. AUTO If no trigger signal applied or the trigger signal frequency is less than 25Hz, the sweep will be in the free run mode. NORM If no trigger signal applied and sweep is in a stand-by state, there will be no trace appear. TV-V Used for observing entire vertical picture of television signal. TV-H Used for observing entire horizontal picture of television signal. (Both TV-V and TV-H synchronize only when the synchronizing signal is negative.) Time Base: (29) TIME/DIV Provide sweep time ranges from 0.2 us/div to 0.5 s/div with 20 steps totally. X-Y Use the instrument as an X-Y oscilloscope by setting to X-Y position. (30) SWP.VAR Vernier control knob of the sweep time used when CAL and the sweep time is calibrated to the value preset in TIME/DIV. The sweep of TIME/DIV can be varied continuously when shaft is not in CAL position. Rotate the control knob to CAL position and the sweep time is calibrated to the preset value of the 8

9 TIME/DIV. Counterclockwise rotate the control knob to the bottom to delay the sweep by 2.5 time or more. (32) HORIZONTAL POSITION Adjust the trace or spot in horizontal position. (31) 10 MAG Magnify 10 by pressing the button. Others: (1) CAL This terminal delivers the calibration voltage of 2 Vp-p, 1 khz, positive square wave. (15) GND Ground terminal of oscilloscope mainframe. Procedure 1. Adjust the function generator to provide a sinusoidal signal of 1 khz and amplitude of 3V. 2. You have to get the figure of this signal on the screen of the oscilloscope. To do that, you have to connect the ground of the F.G. (Black crocodile) with the Ground of Channel 1 (Black crocodile) and also connect the F.G. O/P (Red crocodile) with the Channel 1 I/P (Black probe). 3. Change the input frequency to 2 khz, 5 khz, and 10 khz & get the figures. 4. Repeat the previous procedures for different wave forms (square wave, triangular wave).

10 Capacitor Codes Large electrolytic capacitors usually have their values printed on them (e.g., 10 F, 100 F). The small ceramic capacitors in your lab kits have a three-digit code. The first two digits are the significant figures, and the third digit is a multiplier. Take the first two numbers and add the number of zeros indicated by the third number. This is the capacitor value in picofarads (10-9 farad). For example, 102 is 1000 picofards, = 1000 (10-9 ) F, = 1 nf = F. Your lab kit comes with these values: Table 1. Capacitor codes and values The letter following the three numbers indicates the tolerance. Table 2. Letter Tolerance Code Letter Symbol Tolerance of Capacitor 12