Objectives: Unit 1 Lab Assignment 2 Silicon Controlled Rectifier (SCR) Operation 1. To verify the operation of SCR using DC triggering. 2. To demonstrate the phase control operation of SCR using AC triggering. Procedures: 1. Research the datasheet of 2N1599 SCR and fill the following table 1 at 25°C. Parameter IT(RMS) Forward current RMS IH - Holding current VDRM-Peak forward blocking voltage IGT -Gate trigger current (typical) IDRM - Peak forward blocking current VTM - Forward on voltage (typical) Table 1: Specifications of EC103D1 SCR Part I: SCR Operation – DC Triggering Value 2. Construct the circuit as shown in the Figure 1. (use jumpers as a switch) VCC 12V R1 680Q R2 10ΚΩ Lamps can be found under Indicators >> Lamp 12V 10W Anode D1 S1 Gate 2N1599 SCRS cane be found under Diodes >> SCR Key = Space Cathode Switches can be found under Basic >> Switch >> SPDT Figure 1: SCR DC Triggering 3. Connect the gate switch (S1) to R2, and then run the simulation. Do not stop the simulation until you complete table 2. 4. Measure the voltage at the gate terminal and record the measured value in the first row of the table 2 under gate voltage. 5. Measure the voltage between anode and cathode of the SCR and record the measured value in the first row of the table 2 under SCR voltage. 6. Indicate the condition of the SCR whether it is on or off based on the lamp condition. 7. Change the position of the switch in the order as indicated in table 2 below and repeat steps 4 through 6. Gate connection Gate Voltage (VG) SCR Voltage (VAK) SCR/Lamp condition (On/Off) R2 R1 R2 Table 2: Voltage measurements and condition of SCR Part II: Phase control of SCR - AC Triggering 1. Modify the previous circuit as shown below. Modify the number of turns to 12:0.5:0.5 by double clicking on the transformer ✗SC1 V1 120Vrms 60Hz 0° R1 1.4ΚΩ 12V 10W T1 000000• 7ΚΩ Key=A R2 12:0.5:0.5 0% Transformers can be found under Basic >> Transformers >> 1P1S_Tapped C1 1μF (y) D1 2N1599 Ext Trig ΟΙ Figure 2: SCR Phase control - AC Triggering 2. Turn the potentiometer (R2) to 0%, which represents the firing angle to be approximately 180º. Then Run the simulation. a. Since the firing angle is 180º, no power delivered to the lamp and it should be off. 3. The signals on the oscilloscope should be as shown below. Blue one across SCR & Red one across lamp (separate both signals so you can see them clearly). Oscilloscope-XSC1 < Time Channel_A Channel_B T1 0.000 s 0.000 V -0.000 V T2-> T2-T1 0.000 s 0.000 s 0.000 V 0.000 V -0.000 V 0.000 V Timebase Channel A Channel B Scale: 10 ms/Div Scale: 20 V/Div Scale: 20 V/Div X pos. (Div): 0 Y pos. (Div): 1 Y pos. (Div): -1.8 Y/T Add B/A A/B AC 0 DC O Reverse Save Ext. triggerO Trigger Edge: FZA Ext Level: 0 V AC 0 DC│||-|| O Single Normal Auto None Tauveu Figure 3: Oscilloscope waveforms 4. Change the potentiometer in steps of 25%, take the screenshot of the oscilloscope image (use snipping tool), and insert below. Potentiometer @ 25%: Potentiometer @ 50%: Potentiometer @ 75%: Potentiometer @ 100%: Answer the following Experiment Questions: 1. Before firing, the voltage from anode to the cathode is a. ον 2. If the gate is made on. b. Approximately Equal to Vcc. when the anode and cathode are forward-biased, the SCR turns a. Negative 3. The SCR will b. Positive when the gate potential is removed and the anode/cathode are forward- biased. a. Remain on b. Turn off 4. When the SCR is off, the voltage from the anode to ground is a. Close to VCC b. Near O 5. The SCR will turn off when the current flowing through it drops below the value./n Abstract: Introduction: Procedure: Analysis & Results: A brief description of the experiment. The abstract should not exceed four or five sentences. In your own words, motivate the experiment and give a concise summary of the theory involved, including any mathematical detail relevant to later discussion in the report. List and describe the steps for the practical lab. A schematic of the experimental setup is also required. This section should include all raw data collected, e.g., voltage and current readings. All results are to be presented in both tabular and graphical form. All tables must have titles and all figures must have brief captions. Clearly show your analysis steps and any calculations used leading to your Analysis & Results: Conclusion: required. This section should include all raw data collected, e.g., voltage and current readings. All results are to be presented in both tabular and graphical form. All tables must have titles and all figures must have brief captions. Clearly show your analysis steps and any calculations used leading to your results and conclusions. This section should reflect your understanding of the experiment conducted. Important points to include are a brief discussion of your final results, an interpretation of the actual experimental results as they apply to the objectives of the experiment set out in the introduction should be given. Also discuss any problems encountered and how they were resolved.