Rezolvmee Eng 30 04 2016 [608032]

Nr.1
1.The absolute voltage standard
2.Current dividers -theshunt
3.TDM based wattmeters
4.There areavailable 2voltmeters V1and V2with thefollowing characteristics:
V1- Un=25, 50,100, 250V,c=I
V2-Un=30, 100, 300V, +-1.5%cit+-1%fs
Find out
a)The voltmeter that measure 120V with better accuracy
b)Write themeasurement result U+-~Ulim, U+ellm
~\j-::.\LQ\J –i>1\),-\> Uo\I
(\}'l–:>300 '-J
,6U t\_ Q.U"" l•'l.\o ".:\ ·b\j "2\\
\/1~Q= – \00 =t> t::.v– :2- :!.2.\\ \,.::'j) ~k.1J =.-\o.o~ -lollll2. 000}
UI\.y ""00 "00 I I) A'U/ I6{':I
\{'l.~' .6U::l,51L ~~i\j~= I\S·~2.. ;-~;~\g+~='1IRY"'»)h\l ~~I",-_~I'?
JOQ ~~O 1\.00 ~c'O I.. ~ ,-••••~"'=40'
'Zh-\lL'>~~\I\ >~ "\~~ t>..0.c.w""'~'¢
~ IJ.tbUt:…=\~±.2.S'J~~ \'2.0.±. 2,o26t,.
Nr.2
1.The conservation current standard based onnuclear magnetic resonance
2.Voltage dividers -theRCdivider
3.Hall effect based wattmeters '1""~~Pt 1.\;\~ •.lQAr
4.Two currents aremeasured with 2different ammeters: 11=12A with A1(c=1.5%) and 12=5A with
A2(+-2.5% read+-l% fs.Find out:
The absolute errors that affect thetwo measurements
The current that hasbeen measured with thebest accuracy
-)e.::i~'tl ~~~~ l~~"""A!'= :::t~l.:r. I\~.24'=0~A-'\ .1.:\0.~ ••..~ ~Q l'o/' I
– ]:2..-t\~~.::::1.S' E-\-!L-:0'"to(),'.:O\ 1'b\A.b.L.t.: 2-"lOQ l~'O A.t)~ ~.o,'

Nr.3
1.
2.
3.
4.
Nr.4
l.
2.
3.
4.The absolute resistance standard
Attenuators -theTattenuator (a=20bD, Rc=7Sohms)
Thermal wattmeters
Avoltmetertc=LS, Un=10Y) isverified bycomparing with aanother voltmeter with higher
accuracy. There areavailable 2instruments:
Vl- Un=2SV, c=0.2
V2-Un=20V, +-O.S% +-2digit (2000 counts)
Find out
c)The better instrument
d)Draw theerror graph forthevoltmeter V2
b\j _<'\j _-(' eu t1A\d~~ /1"0\,.)C:l\S::..•..:.-:.:kOt) ::0~\):::- \":"-';: – ,:~~(''' :-')t.1\.:J! Ul•.~.. ~:::"U
U~ ~~O l~~ ~
~ut Ol.V~~ cs- " ~~ S-c..~()1..~__ "'~•••.)b\)~='…:–: -':O,O{'v:) ~h.A" IJ'l.ooe.-U
'\ U~~ ~C~ ~oo
. '\j_.~ c\o\l+1…roo.e:l _t:/J~l, _ ~o\j+t~:=.
,~Oll. ~D\~' – ~ – rv c.1i.~ -""'i"\ f..t)o – "'X)••.•….A\
'fI.I l()~ ~1)0 1..C0..::> v 'P"""\J. c;l 2-. _ \J~~' ":)
o~11 ._t. ,,~ ~ /
-=z-:: 0,':) 4-iO\i". – _..-
'f.~' ~. _'1(,~….~tn!) ~:~(;~•..c'"~H.O.\I.l \IJ"''''')~~
r;~~'S/u–v r"'…. ,\lo\j ~
The absolute capacitance standard \I~
Attenuators -thePIattenuator (a=SdB, Rc=600 ohm)
Digital multiplier based wattmeters
Two ammeters areused forcurrent measurement:
Aic=L, In=2SmA, SOmA, 100m A,
A2c=O.5, In=100mA
Find out:
The error graphfor themeasuring domain 0-100mA ,
Whicghinstrument isbetter tomeasure 2SmA
ht, .-.tM.k\e,):\'0\I
C!."~- t..fJ:> :;;.)~..l\;: – ~-'t ,,~-:::. \0e.,I…~\
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