Measurement technology textbook problems

Click For Summary
SUMMARY

This discussion focuses on various measurement technology problems, including the Wheatstone bridge circuit, three-phase power measurement using the Aron connection, resistance measurement via the V-A method, and DC voltage measurement with different voltmeters. Key specifications include a power meter with I(n) = 3 A and U(n) = 300 V, and voltmeters with varying accuracy classes and measurement ranges. The discussion emphasizes the importance of understanding circuit configurations and measurement errors to achieve accurate results.

PREREQUISITES
  • Understanding of Wheatstone bridge circuit principles
  • Knowledge of three-phase power measurement techniques, specifically the Aron connection
  • Familiarity with resistance measurement methods, including the V-A method
  • Proficiency in interpreting oscilloscope waveforms and phase differences
NEXT STEPS
  • Study the Wheatstone bridge circuit and its applications in electrical measurements
  • Research the Aron connection method for three-phase power measurement
  • Learn about the V-A method for resistance measurement and its systematic errors
  • Explore techniques for analyzing oscilloscope waveforms and calculating phase differences
USEFUL FOR

Electrical engineering students, measurement technology professionals, and anyone involved in circuit design and analysis will benefit from this discussion.

NotFivehead
Messages
3
Reaction score
0
Homework Statement
Measurement technology problems
Relevant Equations
There is no single solution because there are multiple problems
1) Describe the Wheatstone bridge circuit and its condition for balance

2) What is shown in the figure? Explain its operating principle. Derive the relationship between the mechanical and electrical parameters.

3) We are measuring three-phase power using the Aron connection (2-wattmeter method). The power meter specifications are: I(n) = 3 A, U(n) = 300 V, cosφ(n) = 1, scale range = 150°, α₁ = 60°, α₂ = 72°, p(0) = 0,2.
a) What is the application condition for this connection method?
b) What is the active power consumption of the load?
c) What are the reactive and apparent power consumptions of the load?

4) We are measuring resistance using the V-A method. The voltmeter's measurement range is 50 V, and the ammeter's is 1,5 A. The measured voltage is 24 V, and the measured current is 0,8 A. The voltmeter's internal resistance is characterized by 2000 Ω/V, and the ammeter's internal resistance is 0,5 Ω. Both instruments have an accuracy class of 0,5.
a) Determine the measured value of the resistance!
b) Specify the circuit configuration that results in smaller systematic measurement error! Justify your choice! What causes this error?

5) We are measuring a DC voltage of U(measured) = 3 V using the following instruments:
- Deprez voltmeter, accuracy class h(accuracy class) = 0.5, measurement range U(measurement range) = 10 V
- Electrodynamic voltmeter, accuracy class h(accuracy class) = 1.5, measurement range U(measurement range) = 5 V
- 3½-digit digital voltmeter, error ±(0.2% FS + 2D), measurement range U(measurement range) = 20 V
Which instrument allows the most accurate measurement? Justify your choice with calculations!

6) The following waveform was observed on the oscilloscope screen:
a) What quantities can be measured based on the displayed waveform?
b) What is the phase difference between the two compared sinusoidal voltages?

My notes are in the PDF. I had to translate things from Hungarian, sorry in advance!
 

Attachments

Physics news on Phys.org
I think that you have received a DM by now from the Mentors mentioning that we usually prefer just one problem per thread. It is hard for most folks to respond to so many questions in one thread.

Having said that, I'll try to respond to one of the problems:
NotFivehead said:
Homework Statement: Measurement technology problems
Relevant Equations: There is no single solution because there are multiple problems

6) The following waveform was observed on the oscilloscope screen:
a) What quantities can be measured based on the displayed waveform?
b) What is the phase difference between the two compared sinusoidal voltages?
1750880236940.webp

The problem statement doesn't seem to say that the amplitudes of the two sinusoids are the same. What effect would different amplitudes have on the displayed figure?
 
  • Agree
Likes   Reactions: SammyS

Similar threads

  • · Replies 2 ·
Replies
2
Views
655
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
Replies
2
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 13 ·
Replies
13
Views
4K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 18 ·
Replies
18
Views
7K
  • · Replies 3 ·
Replies
3
Views
13K
Replies
5
Views
5K