* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Voltage Divider/Wheatstone Bridge Lab
Survey
Document related concepts
History of electric power transmission wikipedia , lookup
Electrical ballast wikipedia , lookup
Electrical substation wikipedia , lookup
Power MOSFET wikipedia , lookup
Current source wikipedia , lookup
Power electronics wikipedia , lookup
Surge protector wikipedia , lookup
Schmitt trigger wikipedia , lookup
Alternating current wikipedia , lookup
Stray voltage wikipedia , lookup
Voltage regulator wikipedia , lookup
Switched-mode power supply wikipedia , lookup
Buck converter wikipedia , lookup
Resistive opto-isolator wikipedia , lookup
Voltage optimisation wikipedia , lookup
Current mirror wikipedia , lookup
Transcript
CENG 215 Pre-Lab Exercise Name _____________________ Part 1 - Voltage Divider Review Exercise 1. For each of the voltage divider circuits, calculate by hand the indicated voltages. V1 _________ VX ____________ VAB ________ VBC ______ VAC _______ VA,gnd ________ VB,gnd _________ V2, gnd _____________ V3, gnd _________________ Voltage Divider Learning Object - review Voltage Divider and try the sample problems Voltage Divider Java Applet - use the Java Applet to try out various voltage divider combinations Voltage Divider Worksheet do Questions 2, 3, 4, 5, 6, 7, and 8 Part 2 - Wheatstone Bridge Circuits Single Supply Bridge Circuit 1. For a balanced Wheatstone bridge, the bridge output voltage, VAB, is ______ V. 2. For the Wheatstone bridge circuit shown, assume that resistor R4 represents a resistive type sensor whose nominal resistance is 120 Ω. Assume now that R 4 increases to 125 Ω. Calculate by hand the bridge output voltage VAB (VA – VB) to 3 decimal places and the current through R4. VA = ________ VB = ________ VAB = _________ I4 __________ 3. Change the value of R1 to 125 Ω also (leave R4 at 125 Ω). What is the bridge output voltage now? VAB _________________ 4. Change the value of R1 back to 120 Ω and change R2 to 125 Ω (leave R 4 at 125 Ω). What is the bridge output voltage now? VAB _________________ Part 3: Dual Supply Bridge Circuit with current limiting 1. For the Wheatstone bridge circuit shown below 2 additional current limiting resistors have been added and a ± 12 V supply is used. Calculate by hand: a. The current through R4 with the bridge balanced. b. The voltage drop from point X to point Y, VXY or VBridge. c. Assume now that R4 increases to 125 Ω. Calculate by hand the bridge output voltage VAB (VA – VB) and the current through R4. d. Calculate the bridge sensitivity S (defined as the change in output/change in input). The units will be mV/Ω. I4 - balanced VXY VAB I4 - unbalanced Using the value of S, determine VAB if R4 changes to 135 Ω. S VAB ________ 2. R4 is assumed to be a resistive sensor with a maximum current rating of 25 mA. Is this sensor in danger of overheating? YES/NO Why? Part 4: Wheatstone Bridge with Balancing Circuit 1. Calculate the range of adjustment for the balancing circuit. Range from ____________ to ______________ 2. What will happen to the range of adjustment if the 3.9 kΩ resistor is changed to 4.7 KΩ ? Answers Part 1 1. V1 = 8.17 V, VX = 4 V 2. VAB = 4 V, VBC =6 V, VAC =10 V 3. V2,GND = 3.2 V, V3,GND = 5.76 V Part 2 1. 2. 3. 4. VA,GND = 9 V, VB,GND = 3 V VAB = 0 V VA = 6 V, VB = 6.122 V, VAB = - 0.122 V, I4 = 49.0 mA VAB = 244 mV VAB = 0 V Part 3 I4 - balanced 21.4 mA VXY 5.14 V VAB -52.0 mV VAB = -156 mV Part 4 1. Range 91.4 mV to – 91.3 mV 2. Range decreases 75.9 mV to – 75.9 mV I4 - unbalanced 21.0 mA S - 10.4 mV/Ω