anglicky v odborn ch p edm tech support of teaching technical subjects in english n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Anglicky v odborných p?edm?tech "Support of teaching technical subjects in English “ PowerPoint Presentation
Download Presentation
Anglicky v odborných p?edm?tech "Support of teaching technical subjects in English “

Loading in 2 Seconds...

play fullscreen
1 / 10

Anglicky v odborných p?edm?tech "Support of teaching technical subjects in English “ - PowerPoint PPT Presentation


  • 50 Views
  • Uploaded on

Anglicky v odborných předmětech "Support of teaching technical subjects in English “. Tutorial : Mechanic - electrician Topic : Electric measurement the 2nd. y ear Measuring devices 3 Prepared by: Ing. Jiří Smílek.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Anglicky v odborných p?edm?tech "Support of teaching technical subjects in English “' - lola


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
anglicky v odborn ch p edm tech support of teaching technical subjects in english

Anglicky v odborných předmětech"Support ofteachingtechnicalsubjects in English“

Tutorial: Mechanic - electrician

Topic: Electric measurement

the 2nd. year

Measuringdevices 3

Prepared by: Ing. Jiří Smílek

Projekt Anglicky v odborných předmětech, CZ.1.07/1.3.09/04.0002

je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.

measuring instruments basic properties of measuring instruments
Measuring instruments - basic properties of measuring instruments
  • Measuring range:
    • Measuring range ​​reflects the range of values ​​within which the instrument measures with the required accuracy
    • Usually the measuring range coincides with a full scale,
  • Instrument sensitivity :
    • The sensitivity of the device indicates how the deflection of the hands responds to the unit of the measured values.
  • Constant device for
    • is the reciprocal of sensitivity;
    • expresses the size of the measured variables at one scale interval.
    • formula
    • unit V/div, A/div, V . A/div
measuring instruments basic properties of measuring instruments1
Measuring instruments - basic properties of measuring instruments
  • Changing the measuring range:
    • DC
      • Ampere meter– shaft
      • Voltmetr– ballast
    • AC - also
      • Ampere meter– measuring transformer current - MTP
      • Voltmeter-measuring transformer voltage-MTN
  • Calculation of constants:
    • Shunt, ballast - n times increases the range
    • kP = n k
    • MTP - transfer of the transformer p= I/5A
      • Conversion constant transformer
      • KT =p kA
    • MTN - transfer of the transformer p= U/100V
      • Conversion constant transformer
      • KT =p kV
    • W – meter
      • k= range U x range I / number of scale intervals
measuring instruments basic properties of measuring instruments2
Measuring instruments - basic properties of measuring instruments
  • Accuracy of measuring instruments:
    • expresses the class of accuracy.
    • according to standard: 0,05, 0,1, 0,2, 0,5, 1, 1,5, 2,5 a 5.
    • These numbers indicate the measured values ​​of variables leaving the maximum deviation from the actual size, in% of measuring range
    • To measure accurately, the deflection of the hands must be measured in the last third of the scale.
    • formula
    • Overload
      • Overload means the multiples of the rated current or voltage, that the measuring instrument will last for a period of time without damage
        • voltmeters doubled,
        • ammeters tenfold,
measuring instruments basic properties of measuring instruments3
Measuring instruments - basic properties of measuring instruments
  • Power consumption devices:
    • Power necessary to achieve full deflection of the hands
    • Overload
      • Overload means the multiples of the rated current or voltage, that the measuring instrument will last for a period of time without damage
        • voltmeters doubled,
        • ammeters tenfold,
  • Rapid stabilization of displacement of the hands:
    • Reading measurement values ​​- after stabilization of the position of the hands -> longer measurement time.
    • Prevention - damping oscillation rotation of the system.
measuring instruments basic properties of measuring instruments4
Measuring instruments - basic properties of measuring instruments
  • Errors of measuring instruments:
    • influencing variables, which can alter the measurement data. They are for example:
      • ambient temperature,
      • strange magnetic fields,
      • position of the device,
      • frequency,
      • wave alternating current,
      • influence of ferromagnetic bar
  • Reference conditions
    • are the sum of the reference values ​​given by the instrument manufacturer for each influence quantity,
  • The reproducibility of measurements
    • Each correct measurement must be reproducible.
    • This means that repetition with a certain measurement by the same device under the same conditions we get the same results.
activities for students questions
Activities for students–questions
  • Describe what is a measuring range
  • Write how the measuring range is related to the scale
  • Describe what is the instrument sensitivity
      • Write a formula
  • Describe what is a constant unit
      • Write a formula
activities for students questions1
Activities for students–questions
  • Write how to express accuracy of the meter
  • Name the class of accuracy according to the standard
  • Describe what we have to watch to gauge accuracy (as far as possible)
activities for students questions2
Activities for students–questions
  • Write what is meant by overload (thus how we state it)
  • Name some variables affecting the measurement accuracy
  • Describe what we must do, in order for us to repeat measurements to achieve the same conditions
bibliography
Bibliography
  • Mužík, J. Management ve vzdělávání dospělých. Praha: EUROLEX BOHEMIA, 2000. ISBN 80-7361-269-7.
  • Operační program Vzdělávání pro konkurenceschopnost, ESF 2007 – 2013.
  • Dostupné na: http://www.msmt.cz/eu/provadeci-dokument-k-op-vzdelavani-pro-konkurenceschopnost
  • Učebnice Elektrická měření – Ing. Pavel Vylegala, SŠE Ostrava, 2006
  • Učebnice Elektrické měření – SNTL, 1981
  • Elektrotechnika - Laboratorní cvičení pro bakalářské studium - Doc. Ing. Miloš Hammer, CSc.