Download Lab 1 - UTeM

UNIVERSITI TEKNIKAL MALAYSIA MELAKA
FAKULTI KEJURUTERAAN ELEKTRONIK DAN
KEJURUTERAAN KOMPUTER
BENP 2183
ELECTRONIC INSTRUMENTATION
LAB SESSION 1
MEASUREMENT ERROR
Prepared by:
Norizan bin Mohamad / Zahriladha Zakaria
Industrial Electronics Department, FKEKK
(December 2004)
1.0 OBJECTIVES
This experiment is designed to help students to :
a) use DMM to measure DC voltage and current of a circuit.
b) analyze and understand the error introduced during measurement.
c) explain the causes of measurement errors.
2.0 EQUIPMENTS
1)
2)
3)
4)
Digital Multimeter (DMM)
DC Power Supply
Resistor : 1 k - 2 units
Project Board
3.0 PROCEDURES :
3.1 PART A : DC Voltage Measurement
1.
Measure and record the expected resistance values of the two resistors using
DMM.
2.
Construct the circuit in Figure 1.
R1
A
Vin
I2
R2
Vout
B
Figure 1
3.
Set the input voltage Vin = 1 V. Using DMM, measure and record the output
voltage across R2 .
4.
Increase Vin by 1 V. Measure and record the output voltage across R2 .
5.
Repeat Step 4 until Vin = 10 V. (Write down your measurement in a table)
6.
Calculate the expected voltage across R2 for all the input voltages, Vin in
Step 5 . (use the expected resistance value of R1 and R2 )
7.
For each measurement and expected values in Step 5 and 6, calculate the
absolute error, % error, relative accuracy, and % accuracy. What is the
average % accuracy of your DMM ?
8.
Draw a graph of measured output voltage vs. input voltage from your data in
Step 5. How is the relationship between the measured output voltage and
input voltage ? Is there any obvious error seen on your graph ? Is there any
systematic error shown on your graph ? Discuss your observations and
findings.
3.2 PART B : DC Current Measurement
1. Use the resistors and circuit in Part A.
2. Set the input voltage Vin = 1 V. Using DMM, measure and record the current
flow through R2 .
3. Increase Vin by 1 V. Measure and record the current flow through R2 .
4. Repeat Step 3 until Vin = 10 V. (Write down your measurement in a table).
5. Calculate the expected current flow through R2 for all the input voltages, Vin
in Step 4 . (use the expected resistance value of R1 and R2 )
6. For each measurement and expected values in Step 4 and 5, calculate the
absolute error, % error, relative accuracy, and % accuracy.
7. Draw a graph of measured current vs. input voltage from your data in Step 4.
How is the relationship between the measured current and input voltage ? Is
there any obvious error seen on your graph ? Is there any systematic error
shown on your graph ? Discuss your observations and findings.
8. Make conclusion on your observations and findings for the measurement
error in Part A and Part B. Give your opinions on how to reduce the errors.