Iskra MC330 User Manual

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SETTINGS
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2
6
 Measuringcentres
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MC320,MC330,MC350&MC350H‐User’sManua
l
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Maximumdemand(MD)timeconstant(MC350,MC350HandMC330
only)  
Theinstrumentprovidesmaximumdemandvaluesbasedonathermalfunction.Thermalfunctiontime
constantcanbeselectedviakeyboardorviacommunication.
MainmenuSettingsGeneralMDmode/MDtimeconstant
THERMALFUNCTION
Athermalfunctionassuresexponentthermalcharacteristicbasedonsimulationofbimetalmeters.
Maximalvaluesandtimeoftheiroccurrencearestoredindevice.Atimeconstant(t.c.)canbesetfrom1to255
minutesandis6−methermalmeconstant(t.c.=6*thermalmeconstant).
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Example:
Mode:Thermalfunction
Timeconstant:8min.
CurrentMDandmaximalMD:Resetat0min.
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StartingcurrentforPFandPA(mA)(MC350,MC350HandMC330only) 
Atallmeasuringinputsnoiseisusuallypresent.Itisconstantanditsinfluenceontheaccuracyisincreasedby
decreasingmeasuringsignals.Itispresentalsowhenmeasuringsignalsarenotconnectedanditoccursatall
furthercalculationsasverysporadicmeasurements.Bysettingacommonstartingcurrent,alimitofinputsignal
isdefinedwheremeasurementsandallothercalculationsarestillperformed.
Startingcurrentforallpowers(mA) 
Noiseislimitedwithastartingcurrentalsoatmeasurementsandcalculationsofpowers.
Startingvoltageforallpowers 
Noiseislimitedwithastartingvoltagealsoatmeasurementsandcalculationsofpowers.Untilvoltagereaches
userdefinedstartingvoltagelimit,allpowersaresetto0.Usingthreewireelectricalconnections,virtualphase
voltageisusedincalculations.
StartingvoltageforSYNC(MC350,MC350HandMC330only) 
IfallvoltagesarelessthanStartingvoltageforSYNC,thanthecurrentinputsareusedforsynchronisation.Ifall
currentsarelessthanStartingcurrentforPFandPA,thanthesynchronisationisstoppedandthefrequency
resultis0Hz
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Thermal function
01234567891011121314151617181920
Time [min.]
Measured value
Present MD MD peak Input

Iskra MC330 Specifications

General

Brand	Iskra
Model	MC330
Category	Measuring Instruments
Language	English