Snmek 1

Anglicky v odbornch pedmtech"Support of teaching technical subjects in EnglishTutorial :Mechanic - electrician

Topic: Electrical measurementsthe 2nd. YearPerformance measurement DC, AC 1fPrepared by: Ing. Ji Smlek

Projekt Anglicky v odbornch pedmtech, CZ.1.07/1.3.09/04.0002je spolufinancovn Evropskm socilnm fondem a sttnm rozpotem esk republiky.

1Work is a physical quantity. Designation W- el. work (energy) - A mechanical workUnit - 1J = 1 W.s (electrical ) joule (symbol J) - otherPower output equals work done in one second. Designation - P Unit - watt (symbol W). Power output equals work done in one second P=W/t (W;Ws,s)Electrical power output electrical power current I at a voltage UP=U.IUnit - watt (symbol W).

Power Output

Slovnk:Prce fyzikln veliinaVkon jednotka

Frazeologie:Vkon se rovn prci vykonan za jednu sekundu

2Direct current power output- DConly activeP=U*I, Unit - W - wattUsing Ohms law I=U/R (U=RI, R=U/I)P=RI2P=U2/RAlternating current power output- AC1 f - single-phaseapparent S=U*I , unit V.A volt-ampereactiveP=U*I*cos , unit - W - wattidleQ=U*I*sin , unit - var volt-ampere reactiveTypes of power

Slovnk:Stejnosmrn vkonStdav vkon jednofzovtrojfzovpouze innzdnliv jalovreaktannfzor

Frazeologie:Fzorov zobrazen

33 f - three-phaseapparent S=3U*IactiveP=3U U*I*cos idleQ=3U U*I*sin Types of power

Slovnk:Stdav vkon trojfzovinnzdnliv jalovreaktannfzor

Frazeologie:Fzorov zobrazen

4Power output P common namePower appliances P1 power output, which the appliance consumes the motor voltage and currentPower output appliances P2 power output, which the appliance puts out the motor speed and torque

Power input(100 %) Power output (85 %)Supplied power power put outP1 = P2 + P P2 = P1 - P

Types of power

Slovnk:obecn nzevspotebimotor otky kroutc momentdodan vkonvydan vkon

Frazeologie:vkon, kter spotebi spotebovvvkon, kter spotebi vydv5Loss of power- P=P1-P2 - Unit WThe engine heatEfficiency =P2/P1 . 100 - Unit %

Power input(100 %)Power output (85 %)Supplied powerpower put outP1 = P2 + P P2 = P1 - P

Loss of power (15 %)P = P1 P2Types of power

Slovnk:Ztrty vkonu innost teplo

6DC direct current power outputMeasurements using the method:indirect voltmeter and ammmeterRV internal resistance of the voltmeterRA internal resistance of the ammeter

a) I = IA , U = UV UA = UV - RA . IA b) U=UV , I = IA IV = IA - UV / RVP = U . I = UV . IA - RA . IA2P = U . I = UV . IA - UV2 / RV RA > R

Measurement of DC power output

Slovnk:DC vznam zkratkystejnosmrn vkonnepm metodavnitn odpor voltmetruvnitn odpor amprmetru

Frazeologie:Men pomoc nepm metody:

7AC Alternating current power outputMeasurements using the method :direct wattmeter, To check using a voltmeter and ammeter

With the current coil voltageActual power output PsPS = P RAI2 RWAI2RWA coil current resistance meter

Measurement of AC power output1 f

Slovnk:AC vznam zkratkyStdav vkonodpor proudov cvky wattmetru

Frazeologie:zapojen s napovou cvkou ped proudovouMen pomoc pm metody:s kontrolou pomoc voltmetru a amprmetru

8AC Alternating Measurements using the method:direct wattmeter, To check using a voltmeter and ammeter

With the current coil voltageActual power output PsPS = P U2/ RV U2RWURWU coil resistance voltage meter

Measurement of AC power output1f

Slovnk:AC vznam zkratkyStdav vkonodpor napov cvky wattmetru

Frazeologie:Men pomoc pm metody:s kontrolou pomoc voltmetru a amprmetrus napovou cvkou za proudovou

9Name the types of power output: d) e) f)Explain what power input is Explain how you prove a loss of power Write how to calculate the motor efficiency

Activities for students - questions

Vyjmenujte druhy vkonu:DC AC 1 fAC 3 fvkonpkonztrtyVysvtlete co je to pkonVkon dodan spotebiiVysvtlete jak se projevuj ztrty vkonupemuj se v teploNapite jak se vypot innost motoru= P2 / P1, = vkon/ pkon10How can you overload: A current coil wattmeter, A voltage coil wattmeterTwo coils, Even when the hand shows deflection within the scale?

Activities for students - questions

Jak me dojt k peten: proudov cvky wattmetru, napov cvky wattmetru obou cvek, a) i b) Vkon je souin napt a proudu 6=6x1 nebo 1x6c) Pi peten obou cvek wattmetru zrove.

11Muk, J. Management ve vzdlvn dosplch. Praha: EUROLEX BOHEMIA, 2000. ISBN 80-7361-269-7.WikipediePruka elektrotechnika, Europa 2000Elektrick men - E. Viteek, Vl.HOS - SNTL 1978Elektina kolem ns Zdenk Opava Albatros 1981

Operan program Vzdlvn pro konkurenceschopnost, ESF 2007 2013.Available at: http://www.msmt.cz/eu/provadeci-dokument-k-op-vzdelavani-pro-konkurenceschopnost

Bibliography