XITRON XT2640 - Page 168

XT2640OperatingManual 13July2016 Page168of187
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28.2.2.1 PRIMARYVOLTAGEMEASUREMENTACCURACYTABLE
Addrelevanterrorsfromthetablebelowforthemaximumerrorinprimaryvoltagemeasurements(e.g.DC,AC,AC+DC,Rectified,
Peak,Valley,Peak‐Valley).
MAXIMUMSCALINGERRORS
Applytoallresultsasshownbelowasapercentageofthereading
Ifsignalcontainssignificantlevelsatmultiplefrequencies,applytoeachlevel&frequency
Specification SChannelType
A
ChannelType LChannelType WChannelType
BaseScalin
g
Error
Applytoallresults
0.1% 0.03%
0.1%
(0.2%if2msLF/PERIOD)
FrequencyDependentScalingError
ApplytoallresultsotherthanDCor
MAINS
AVIONICS None 0.005% None
LForVLF 0.01% 0.05%
<10kHz F*0.005%
F*0.002%
10k‐40kHz 0.05%+(F‐10)*0.012%
40k‐100kHz 0.41%+(F‐40)*0.025% 0.08%+(F‐40)*0.004%
100k‐1MHz Typically(F/1000)
2
*100% 0.32%+(F‐100)*0.013%
>1MHz Nots
p
ecified T
yp
icall
y

(
F
/
3500
)
2
*100%
Self‐Heatin
g
Scalin
g
Error
Applytoallresults(onlysignificantathighervoltages)
1minutenominaltimeconstant
0.05%*(V
AC+DC
/1000)
2
0.5%*(V
AC+DC
/1000)
2
 0.15%*(V
AC+DC
/1000)
2

TemperatureScalin
g
Error
Applytoallresultsifoutsideof±5Cfromcalibration
temperature
0.005%perCoutsideof±5Cfromcalibrationtemperature
BandwidthLimitScalin
g
Error
ApplyifusingUSERbandwidthsetting
10%*(F/F
BW
)
2
,unspecifiedforF>0.3*F
BW

MAXIMUMFLOORERRORS
ApplytoallresultsasshownbelowinVolts(generallyonlysignificantatlowinputlevels)
Specification SChannelType
A
ChannelType LChannelType WChannelType
BaseFloorError
Applytoallresults
1.8mV 450µV 45µV 1.8mV
DCFloorError
ApplytoDCandRECTIFIEDresults
ApplytoAC+DCresultsaftermultiplyingbyV
DC
/V
AC+DC

3mV 1mV 100µV 5mV
ACFloorError
ApplytoAC,AC+DC,and
RECTIFIEDresults
MAINS,LF,VLF&F
BW
≤10kHz 100
µ
V
/V
RDG
100
µ
V
/V
RDG
4
µ
V
/
V
RDG
200
µ
V
/V
RDG
AVIONICS&F
BW
≤50kHz 300µV/
V
RDG
300
µ
V/
V
RDG
8
µ
V/V
RDG
650
µ
V/
V
RDG
Otherwise 1.1mV/V
RDG
1.1mV/
V
RDG
11
µ
V/V
RDG
1.5mV/
V
RDG
PeakFloorError
ApplytoPK,VLYandPK‐
VLYresults
MAINS,LF,VLF&F
BW
≤10kHz 40mV 40mV 8m
V
60mV
AVIONICS&F
BW
≤50kHz 75mV 75mV 11m
V
125mV
Otherwise 125mV 125mV 17mV 175mV
CommonModeError
ApplytoAC,AC+DC,andRECTIFIEDresults
ApplyusingvoltageonVLOterminalrelativetochassis
ground.Errorhas90°phaseshifttocommon‐mode
voltage
1µVperV.Hz
(11.5mV@230V/50Hz)
100nVperV.Hz
(1.15mV@230V/50Hz)
700nVperV.Hz
(8.05mV@230V/50Hz)
A
djacentChannelError
ApplytoAC,AC+DC,andRECTIFIEDresults
ApplyusingadjacentchannelALOorVLOterminal
voltagerelativetochassisground.Errorhas90°phase
shifttoadjacentchannelvoltage
300nVperV.Hz
(3.45mV@230V/50Hz)
30nVperV.Hz
(345µV@230V/50Hz)
210nVperV.Hz
(2.415mV@230V/50Hz)
28.2.2.2 SECONDARYVOLTAGEMEASUREMENTACCURACYTABLE
Specification SChannelType
A
ChannelType LChannelType WChannelType
CrestFactorError (Total FloorError fromprecedin
g
tableforPKresults)/V
AC

FormFactorError
(
TotalFloorErrorfrom
p
recedin
g
tableforAC+DCresults
)

/
V
RECTIFIED

Inter‐ChannelError
For120°betweenequalamplitudes
(RelevantVoltageErrorsfromprecedingtableattheinter‐channelvoltage)+0.0015%*F
HarmonicorSpectrumError

ACVoltageErrorsfromprecedingtableatVandFoftheharmonicorspectrumpoint
+(H/N)
2
*0.3%ofreading
+(ifnotfundamental)frombelowusingthefrequencyoftheharmonicorspectrumpoint
<10kHz 0.01% of
V
AC+DC
0.006% of
V
AC+DC
0.015% of
V
AC+DC
10k‐115kHz 0.05% of
V
AC+DC
0.03% of
V
AC+DC
115k‐435kHz NotAvailable 0.08%ofV
AC+DC

Inter‐ChannelFundamentalPhaseError 0.02°+0.15°*F 0.01°+0.07°*F
Harmonic‐FundamentalPhaseError(typical,
BANDWIDTHconfi
g
uredasUNFILTERED
)

0.02°+0.1°*F+0.001°*H 0.02°+0.03°*F+0.001°*H
%THDError
Errorsshownareallexpressedin
%THDunits

(0.005+0.000025*N)*%THD+0.00005*N*√N
+frombelowusingthefrequencyofhighestincludedharmonic
<10kHz 0.025+1.25/V
AC
0.015+1/
V
AC
0.015+0.2/
V
AC
 0.03+1.5/
V
AC
10k‐115kHz 0.15+3.5/
V
AC
0.15+0.35/
V
AC
 0.06+4/V
AC
115k‐435kHz NotAvailable 0.15+4/V
AC

28.2.2.3 EXAMPLES
Example1
ForanAtypechannelthemaximumerrorofameasurementoftheAC+DCvoltageofa230Vrmssignalat50Hzisaworstcaseof
±0.034%ofreadingascalculatedby:
ScalingErrors:
BaseScaling=±0.03%
FrequencyDependentScaling=NoneatMAINS
Self‐heatingScaling=±0.05%*(230V/1000)
2
=±0.002645%
TemperatureScaling=nonewithin5Cofthecalibrationtemperature
BandwidthLimitScaling=nonewhenusingAUTO‐TRACK