2011.10.05.. TÁMOP – 4.1.2-08/2/A/KMR-2009-0006 1 Development of Complex Curricula for Molecular Bionics and Infobionics Programs within a consortial* framework**
Consortium leader
PETER PAZMANY CATHOLIC UNIVERSITY
Consortium members
SEMMELWEIS UNIVERSITY, DIALOG CAMPUS PUBLISHER
The Project has been realised with the support of the European Union and has been co-financed by the European Social Fund ***
**Molekuláris bionika és Infobionika Szakok tananyagának komplex fejlesztése konzorciumi keretben
***A projekt az Európai Unió támogatásával, az Európai Szociális Alap társfinanszírozásával valósul meg.
PETER PAZMANY CATHOLIC UNIVERSITY
SEMMELWEIS UNIVERSITY
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Peter Pazmany Catholic University Faculty of Information Technology
ELECTRICAL MEASUREMENTS
Laboratory exercises
www.itk.ppke.hu
(Elektronikai alapmérések)
(Laboratóriumi gyakorlatok)
Tihanyi Attila
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Electrical Measurements: Laboratory exercises
• Meter and Si system
• LabView programming
• Measurements in DMM
• Oscilloscope measurements and function generator
• Spectrum and its measurement
• Blood pressure
• Hearing curve
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Contents
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Electrical Measurements: Laboratory exercises
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The meter story and Si system
• The first etalon of length in 1791 Franch Natinal Assembly
• BORDA, CONDORCET, LAGRANGE, LAPLACE és MONGE handiwork
• The first International etalon realization form may 20 1875
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The „Comíté International des Poids et Mesures; CIPM „
• The first meter etalo
n TRESCA and István Kruspér hadiwork
• Material of tis meter etalon is Platina(90%) Iridium(10%)
• Environment is 0 °C and 750 tor airpressure
• This definicion accepted which industrial standerd widtout United Kingdom and United State of America
• Ordinal Number of 14 is a Hungarian etalon which originally shorter1,3μm
• The national benchmark feet of the Hungarian National Bank was kept.
• Many technical problems were the regular verification by the Paris compare witk original meteretalon had to be carried out.
Electrical Measurements: Laboratory exercises
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István Kruspér (1818-1905)
His main scientific interest was the subject of geodesy. He collaborated in the preparation of the bill to accept the meter and the kilogram as the only legal measuring units. He constructed devices to measure the
reference standard. On his recommendation the government set up the Committee of Weights and Measures, the predecessor of the National Office of Weights and Measures, which he headed for 16 years. From 1879 he was a member of the Paris-based International Committee of Measures for 15 years
After finishing his high school education, Kruspér first studied law, then attended the Politechnisches Institut in
Vienna. After obtaining his diploma in engineering, within a few years he started his activities as a lecturer at the József Trade School .
Electrical Measurements: Laboratory exercises
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Reproduce meter etalon
• The comparisons showed more errors.
• The scratches on the uncertainty of the reading: 0.2pm
• The continuously variable crystal structure causes a change in length of meter.
• The largest Hungarian-meter standard deviation 3μm
• The size of difference in comparison 10-7
• The biggest problem is if the original etalon fails. It becomes impossible to measure longitude.
• Other natural chin should be used to determine the length concept
• Be reproducible in the laboratory of the etalon production
Electrical Measurements: Laboratory exercises
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Definition of metre
• The most precise time can be determined. (According to the sources of some of today's precision is less than 10-16!).
• Early as 1906 M. PLANCKOT and in 1961, C. H Towers proposed of time the length granted. They suggested that the unit length can determine the speed of light and time. These are the universal
constants of nature.
Electrical Measurements: Laboratory exercises
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Bay Zoltán (1900-1992)
Zoltán Lajos Bay was a Hungarian physicist, professor, and engineer who developed microwave technology,
including tungsten lamps. He was the first person to observe radar echoes from the Moon. From 1930, he worked at the University of Szeged as a professor of theoretical physics.
He determined the speed of light was conducted from 1965.
In his work on the basis of the value of the speed of light 299 792 458 m/s in 1972.
This value is the definition since 1975. (Conférence Générale des Poids et Mesures; CGPM)
Electrical Measurements: Laboratory exercises
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Definition of meter
The current definition of longth is:
1 meter is the distance which the light
1/299 792 458 s passes in vacuum
This is a very precise definition. The maximum deviation 10-12 Some researchers even talk of less than 10-15
Any electromagnetic wave can be used for this definition, but in practice it is used He-Ne lasers.
The definition is good if:
reproduse, precise, and simplisity
Electrical Measurements: Laboratory exercises
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Practical Tasks
Measure the length of the corridor with bar measure Reduce the measurement errors
Make a note of the circumstances and the method of measuring instrument
Grouping according to differences in incidence regular and random Measure the resulotion of his eyes with
black and white, and colors pictures Calculate the resolution of the eye
Determine the difference, if the measurement error of 1% or 5%
⎟⎟⎠
⎜⎜ ⎞
⎝
= ⎛
eyeshot
picture in
pixelsize arctg
resulotion
eye _ _
_
Electrical Measurements: Laboratory exercises
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LabView basics.
Labview is a programming languge with
• Graphical input and output surface (front panel)
• Input controlls with same different variable types
• Output indicators with same different variable types
• Graphical programming surface (block diagram)
• Graphical program structures and substructures (for, while, if, switch, event)
• Graphical variables (boolean, integer, float, double, array, structure, vector, etc)
• Graphical operators (addition, multiplication etc)
• Graphical functins (sin, cosin, sqrt, log etc)
Electrical Measurements: Laboratory exercises
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The Front panel
Numeric Input control
Boolean Input control Graphical
output indicator Window
with menu and buttons
Electrical Measurements: Laboratory exercises
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The Block diagram panel
While cycle
Cycle variable Control
from front panel Window with menu
and buttons
Float variable
Simulate Signal Funtion
Indicator to front panel
Control from front
panel
Cycle stop if true Structure array
variable Electrical Measurements: Laboratory exercises
Electrical Measurements: Laboratory exercises
Control palette and function palette
Use the Controls palette to place controls and indicators on the front panel. The Controls palette is available only on the front panel.
Select Window Show Controls Palette or right-click the front panel workspace to display the Controls palette. You also can display the Controls palette by right-clicking an open area on the front panel.
Tack down the Controls palette by clicking the pushpin on the top left corner of the palette.
Use the Functions palette, to build the block diagram. The Functions palette is available only on the block diagram. Select Window Show Functions Palette or right-click the block diagram workspace to
display the Functions palette. You also can display the Functions palette by right-clicking an open area on the block diagram. Tack down the Functions palette by clicking the pushpin on the top left corner of the palette.
Flat sequence
Condition examination
While cycle
For cycle Shift registers
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Electrical Measurements: Laboratory exercises
Programming structures on function palette
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Type of variables
Creating 2D array Scalar types
Electrical Measurements: Laboratory exercises
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Numeric operators
Electrical Measurements: Laboratory exercises
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Boolean operators
Electrical Measurements: Laboratory exercises
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Functions
Electrical Measurements: Laboratory exercises
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The program's controls
Electrical Measurements: Laboratory exercises
Run buttons
Continuous run buttons Abort execution
Other buttons on the diagram panel
Execution highlighting buttons Step function buttons
Icons settlement
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Debugging your program
Electrical Measurements: Laboratory exercises
• Finding errors
• Click on broken run button window showing error appears
• Execution highlighting
• Click on execution highlighting button, data flow is animaed uding bubbles. Values are displayed on wires.
• Probes
• Right-click on wire to display probe and it shows data as it flows through wire segment
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Tasks
Electrical Measurements: Laboratory exercises
• Create an on / off LED and a process which converts the km/h value at the m/s
• Create a dice program, any numeric indicator. A program create a new random value every button push. If the result is equale to 6 then light a red led.
• Place the front of a numeric indicator, green LED and a switch.
Measure the time delay ability of people accuracy. The user must press the button for 1 second. If the result is more accurate than 1% of the green
LED indicates.
• Create a sine wave generator and a two voltage meter instrument. Be controlled by the generator output voltage and frequency. One of the
voltmeter show that the effective voltage and the other is the peak voltage.
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Tasks
Electrical Measurements: Laboratory exercises
• Make a circuit modeling program, as shown below
2
1
R
R I U
g= + U
1= I ⋅ R
12
2
I R
U = ⋅
Boundary conditions Ug = 0 … 10 V
R1 = 1 … 10 ohm R2 = 1 … 10 ohm
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Basic quantums in electronics
Charge Q C Coulomb
Current I A Amper
Tension U V Volt
Power P W Watt (effectual)
VA VoltAmper (reactive)
Energy W Ws WattSecond
J Joule
Resistance R Ω Ohm
Conduct G S Siemens
Inductivity L H Henry
Capacity C F Farad
Time t s Second
Frequency f c/s Cycle/second
Hz Hertz
ω rad/s radián/second (helmholtz) Electrical Measurements: Laboratory exercises
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Electric Basic Measurements
The National Instruments ELVIS system included one Digital Multi Meter (DMM)
Instrument used to
• AC/DC voltage measurement with high input impedance
• AC/DC current measurement with low input impedance
• Resistance measurement with constant current
• Diode test and audible continuity
• Capacitance measurement with low frequency constant current
• Electrical capacity measurement with DC plus low frequency constant current
• Inductance measurement with low frequency constant current Warning: The current measurement input is very low impedance and use it the voltage measurement is failure cause.
Electrical Measurements: Laboratory exercises
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Electric Basic Measurements
The DMM including 3 pins to contact
• „COM” is a Common or gound
• „VΩ Diode” for a Voltage, Resistance, and Forward voltage measurement
• „A” for contact a current measurement in low current mode Limitation
• Voltage limit is 60V in DC and 20Vrms in AC mode
• In „A” pin maximum 2 Ampers
Electrical Measurements: Laboratory exercises
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The first task
Resistance measurement:
Start the instuments using DMM icon (double click)
• Push the RUN icon for start the measurement
• Connect the two input pins for zero
• Select the operation mode with Ω button
• Press the „Null offset” for calibrate DMM
• Connect the resistor to the instrument COM and Ω pins
• Read the result form display.
This is a good result, Observe the display
Electrical Measurements: Laboratory exercises
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Electrical Measurements: Laboratory exercises
Display with bargraph
Operation modes Connections
Acquisition mode
RUN/STOP Null offset
Mode: Select between „Auto”
and „Manual”
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The first task
Perform the test several times and calculate the average of the measurements Try the operation of the instrument, other modes also
• Capacitance mode
• Inductance mode
• Voltage mode
In the inductivity and capacity mode the resistance the DUT+, DUT- should be connected between points
In the voltage mode the resistance the COM, V should be connected between points
Our results give these defective. Observe the display
Electrical Measurements: Laboratory exercises
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Other tasks
Perform other tasks in the previous circumstances Measure the inductance value of each mode
• Resistance mode
• Capacitance mode
• Inductance mode
• Voltage mode
Measure the capacitance value of each mode
• Resistance mode
• Capacitance mode
• Inductance mode
• Voltage mode
Evaluate the reading results, which is how much confidence
Electrical Measurements: Laboratory exercises
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Voltage divider
Electrical Measurements: Laboratory exercises
2 2
2 U I R
U = R = ⋅
2 1
1 1
R R
U R
I U
e = +
=
2 2
1 2 1
2 R
R R
R U I
U ⋅
= +
⋅
=
2 1
2 1
2
R R
R U
U
= +
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Voltage divider with load
Electrical Measurements: Laboratory exercises
) ( 2
2
2 UR I R Rt
U = = ⋅ ×
) ( 2
1
1 1
t
e R R R
U R
I U
×
= +
=
) ) (
) (
( 2
2 1
2 1
2 t
t
t R R
R R
R R U
R I
U ⋅ ×
×
= +
×
⋅
=
) (
) (
2 1
2 1
2
t t
R R
R
R R
U U
× +
= ×
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Training
Electrical Measurements: Laboratory exercises
• Select a piece of 2 x resistance and 1 x capacitor.
• Measure the value of the components with DMM
• Assemble the voltage divider circuit. See figure. R2 smallest then R1.
• Connect the input to the variable power supply.
• Measure the input voltage U1 with DC voltage meter
• Set a 5V voltage
• Measure the output voltage U2 with DC voltage meter
• Check the measurement accuracy of calculation
• A good result difference is less than 1%
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Elvis function generator
Electrical Measurements: Laboratory exercises
The function generator is a device that generates time varying waveforms.
The NI ELVISmx Function generator is generally used to generate a
periodic voltage signal in the form of a sine wave, a triangular wave or a square wave. The function generator output can be obtained via two routes:
the FGEN BNC output channel or the FGEN prototyping board pin
sockets. Shown below is the FGEN SFP, as well as an explanation of the important controls. The FGEN signal is referenced with respect to
GROUND.
Click this icon to start function generator
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The window of function generator
Electrical Measurements: Laboratory exercises
Frequency display Waveform
selector
Waveform parameters
Output selector Frequency
sweep parameters
Set to manual mode
RUN/STOP
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Elvis function generator
Electrical Measurements: Laboratory exercises
Frequency Display: displays the frequency of the output waveform. When the function generator is off, “OFF” is displayed.
Waveform Selectors: allows the user to select what type of waveform is generated. The choices are sine wave, triangular wave and square wave.
Waveform parameters: the characteristics of the output waveform can be selected by the user. These characteristics include: Frequency, peak-to-
peak amplitude, DC offset, duty cycle that is only enabled when square wave is selected as the waveform type, and adjusts the turn-on to turn-off ratio of the wave, and the modulation type which controls the type of
modulation.
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Elvis oscilloscope
Electrical Measurements: Laboratory exercises
The oscilloscope is a device that displays signal voltages as a two-
dimensional graph of electrical potential differences (vertical axis) plotted as a function of time (horizontal axis). Though time-invariant (DC)
voltages can be displayed, this device is commonly used to display time- varying voltage signals. The NI ELVISmx Oscilloscope consists of two channels, Channel 0 and Channel 1, which can automatically connect to up to ten (10) sources.
Click this icon to start oscilloscope
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The screen of the oscilloscope
Electrical Measurements: Laboratory exercises
Scope graph Channel
selector Probe and
coupling Vertical
sensitivity and position
Trigger
Log waveform
Time base Display
measurement Cursor
settings RUN/STOP
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The usage of the oscilloscope
Electrical Measurements: Laboratory exercises
Scope Graph: displays the waveforms specified in Channel 0 and Channel 1 as well as the cursors. The bottom of the scope graph displays various signal characteristics (“CH 0 Meas.” and “CH1 Meas.”). These
characteristics include root mean square (RMS), frequency (Freq) and the peak to peak amplitude (Vp-p). These measurements are only shown if the channel is enabled.
Channel Settings: as previously stated there are two oscilloscope channels Channel 0 and Channel 1. Channel settings allow the user to specify the source signal that will be displayed for each channel. The choices include SCOPE CH 0 and SCOPE CH 1 BNC input channels or AI<0…7> input signal rows. The Enabled box below the channel settings allow the user to specify which channels to display in the scope graph.
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The usage of the oscilloscope
Electrical Measurements: Laboratory exercises
Probe and Coupling: The probe setting is dependent on what kind of probe is being used to measure the signal voltage. In some case the signal being measured is the sum of a time-varying voltage and a DC signal. If the user chooses to display only the AC part of the signal then the coupling setting can be changed to “AC”. This setting will display only the AC part of the signal. The “AC” setting is not available for signals measured with the AI channels.
Vertical sensitivity and Vertical Position: The Volts/Div knob or drop- down menu allows the user to choose the voltage axis scale. The Vertical Position knob or numerical input allows the user to adjust the zero cross.
The user is most likely to use this control when the waveform is the sum of time varying signal and a DC signal.
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The usage of the oscilloscope
Electrical Measurements: Laboratory exercises
Trigger: This oscilloscope features triggered sweeps. A triggered sweep starts at a selected point on a trigger signal, providing a stable display. The scope has three settings: Immediate, in which there is no external trigger signal and the data acquisition begins immediately; Digital, in which acquisition begins on the rising edge or fall edge (Slope setting) of an external digital signal.
Log: allows the user to take a snapshot of the waveform(s) displayed on the scope graph and save the waveform as a .csv file which allows for the
plotting of displayed waveforms in other programs such as Matlab and Excel.
Timebase: The Time/Div control knob and menu allows the user to choose the time-axis scale.
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The usage of the oscilloscope
Electrical Measurements: Laboratory exercises
Display Measurements: Allows the user to select which channel measurements to display at the bottom of the scope graph.
Cursor Settings: allows the user to display up to two cursors on the scope graph. The cursor position is then displayed at the bottom of the scope
graph. The cursors can be moved horizontally by clicking the cursor and dragging it along the time axis. The user can also select which of the two channels, Chan 0 and Chan 1, are associated with the two cursors.
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Next training
Electrical Measurements: Laboratory exercises
• Connect the input to the function generator output.
• Set the generator output sinusoid and 1 Vpp signal
• Measure the input signal with oscilloscope CH1
• Measure the output voltage with oscilloscope CH0
• Turn on both beams simultaneously and to investigate
the phase difference
• Perform the test again
using swap parts (R1 and C1).
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Measure phase differenc
Electrical Measurements: Laboratory exercises
. Measure periode time on zero crossing point
with cursor, for example 2,93ms
Measure nearest zero crossing point in two signal with cursor, for example 2,16ms
Calculate the ratio of two values and multiply the result by 360°.
THIS IS A PHASE DIFFERENT of two signal in degree
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Square Wave Practice
Electrical Measurements: Laboratory exercises
• Connect the input to the function generator output.
• Set the generator output square and 1 Vpp signal
• Measure the input signal with oscilloscope CH1
• Measure the output voltage with oscilloscope CH0
• Turn on both beams simultaneously and to investigate
the phase difference
• Measure the spectrum with dinamic signal analyser DSA
• Perform the test again
using swap parts (R1 and C1).
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Square Wave Practice 2
Electrical Measurements: Laboratory exercises
Set the measurement frequency, so that
C j R1 1
= ω Integrator output
Differenciator output
Measure the results of other frequencies
Compare the measured data
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Elvis Digital Signal Analyser (DSA)
Electrical Measurements: Laboratory exercises
The dynamic signal analyzer is an instrument performs a frequency domain transform of a signal. The NI ELVISmx Dynamic Signal Analyzer consists of a single channel, which can automatically connect to up to ten (10)
ources. It can continuously makes measurements or take a signal scan.
Shown below is the DSA SFP in Figure 10, as well as an explanation of the important controls.
Click this icon to start digital signal analyser
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Elvis Digital Signal Analyser (DSA)
Electrical Measurements: Laboratory exercises
Spectrum display
Waveform display
Input selector
FFT settings
Cursors
Spectrum parameters
RUN/STOP
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Elvis Digital Signal Analyser (DSA)
Electrical Measurements: Laboratory exercises
Spectrum display: displays the frequency domain representation of the input signal with a plot of magnitude against frequency. Also displayed is the Detected Fundamental Frequency (in Hz) based on full harmonic
analysis. The Fundamental Frequency Power is an estimate of the power of the fundamental frequency peak over a span of three frequency lines. The Mode drop down menu specifies whether to display the power spectrum or the power spectral density of the input signal.
Waveform display: displays the input signal in the time domain. Vpk (V) displays the difference between the measured maximum and minimum voltage level of the input signal.
Input Selector: allows the user to specify the source and the expected voltage range of the input signal. The input channel
sources are SCOPE CH <0..1> (see oscilloscope) and AI<0..7>.
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Elvis Digital Signal Analyser (DSA)
Electrical Measurements: Laboratory exercises
FFT Settings: specifies the settings for the fast Fourier transform and averaging options respectively. The options are Frequency span which specifies the measurement range that starts from DC and extends to the selected value; Resolution which specifies length of the time domain
record and the number of samples to be acquired; Window which specifies the time-domain window to use; Mode which specifies the averaging
mode. The choices are Vector, RMS and Peak-Hold; Weighting which specifies the weighting mode for RMS and Vector averaging. The choices are linear and Exponential; and # of Averages which specifies the number of averages that is used for RMS and Vector averaging.
Cursor Settings: These set of controls give the user the choice of enabling measurement cursors (Cursors On) on the frequency domain and time-
domain displays and precise control of a selected cursor (Cursor Select) via the Left and Right buttons.
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The result of square signal
Electrical Measurements: Laboratory exercises
• Square signal frequency 237Hz
• The signal amplitudo 1Vpp
• M1 cursor set to the fundamental frequency
• M2 cursor is show a harmonic frequencies
• df(Hz) = 475,00 is a different of two cursors frequency
• ddBVrms 9,29 is a different of two cursors amplitudo
• These values show the proportion of elements of the Fourier series
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Electrical Measurements: Measurement of voltage and time
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Frequency defined with timing measurement Blood pressure
1 2
t
t a
a t t
dt P P
2
1
=
∫
−Number of heartbeats
(sec) t
(sec) t
N 60
1 2
hb = −
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Blood pressure practice
Electrical Measurements: Laboratory exercises
Korotkof method
Tighten the flow of blood through the blood pressure instrument
Slowly release the air
Listen to the bloodstream
Intermittent tone indicates the
appearance of the systolic pressure value.
Continuous tone indicates the diastolic pressure Read the pressure value of systolic and diastolic
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Electrical Measurements: Measurement of voltage and time
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Nikolai Sergeyevich Korotkov (1874-1920)
Nikolai Sergeyevich Korotkov (Russian: Николай Сергеевич Коротков) (1874 –1920) was a Russian
surgeon, a pioneer of 20th century vascular surgery, and the inventor of auscultatory technique for blood pressure measurement.
Korotkoff sounds are pulse-synchronous circulatory sounds heard through the stethoscope in auscultation of blood pressure using Riva- Rocci's sphygmomanometer.
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Audiometer
Electrical Measurements: Laboratory exercises
Create a program in LabVIEW. A program to issue a separate adjustable height, sound volume. The program lets you reach the threshold of hearing curve.
• Select a measurement frequency and the minimal value.
• Increase the volume and read the value of the volume when you hear
• Repeat the measurements on different frequencies.
• Depict a diagram of the values.
• The measurement is carried out by everyone.
• The results are averaged and compare Békéssy's curve.
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Electrical Measurements: Measurement of voltage and time
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Békéssy's curve.
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Electrical Measurements: Measurement of voltage and time
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Békésy György (1899-1972)
Békésy was born on June 3, 1899 in Budapest, Hungary the first of three children (György 1899, Lola 1901 and Miklós 1903) to Alexander von Békésy (1860–1923), an economic diplomat born in Kolozsvár, and his wife Paula Mazaly (1879–1974) born in Cadavica. He went to school in Budapest, Munich, and Zürich.
He studied chemistry in Bern and received his PhD in physics on the
subject: "Fast way of determining molecular weight" from the University of Budapest in 1926. He then spent one year working in an engineering firm. He published his first paper on the pattern of vibrations of the inner ear in 1928. He was offered a position at Uppsala University by Róbert Bárány, which he dismissed because of the hard Swedish winters.
