CIRCUTOR computer SMART III-Fast Series - Manual (Page 24)

Other Programs� Other programs can be used, such as 1�2�2�4, 1�2�4�8, 1�1�2�2, etc�The
meaningofthenumbers,ascanbededucedfromtheprecedingcases,givesthepowerratio
betweenthefirststage,whichreceivesavalueof1,andthesubsequentstages(2meanstwice
asmuchpower,4meansfourtimesasmuchpower,etc�)�
Theunitcanbeusedtoconfigureprogramsfrom1�1�1�1to1�9�9�9�
4�1�5� Plug and Play�
Whenareactiveenergyregulatorisinstalled,aseriesofparametersmustbeconfiguredfor
itscorrectoperation�Someoftheseparametersmightbedifficulttodiscover,forexample,the
voltagephasesorthecorrespondencebetweenmeasuredcurrentanditsvoltage,aswellas
thecurrenttransformerratio�The Computer SMART III FASTincludesanautomaticprocess,
whichintelligentlyworksoutnecessaryparameterssuchas:
 Connection type: detectstheconnectiontypeusedfromamongthepossibleoptions:
3U �3C, 3U�1C and 2U �1C�
 Phase:identifiesthecorrespondencebetweenthevoltagesandthecurrentsconnect-
ed,regardlessoftheconnectiontypedetectedpreviously�
 Number of stages installed and Program:sequentiallyconnectsallthestagesto
workouthowmanystagesareinstalledandcalculatestheprogram,inotherwords,the
powerratiobetweenthecapacitors�
 C/K: calculatestheratiobetweenthecurrenttransformerandthepowerofthesmall-
eststep�
4�1�6 Connection time (Ton) and Reconnection time (Trec)�
The Connection time, Ton,definestheshortestpossibletimebetweenchangesinthestatus
ofthestages,inotherwords,betweenconnectionsanddisconnections�Therefore,theconfigu-
rationofthisparameterhasadirectimpactonthecompensationspeed,inotherwords,onthe
capacityformonitoringloadchanges�Settingashorterconnectiontimeimprovesthepower
factorcorrectionwhentheloadcanchangequickly�
However,ashorter Tonwillleadtoahighernumberofconnectionspertimeunit,possibly
shorteningtheusefullifeoftheassociatedcomponents(thyristors,capacitors)�Toassessthe
numberofconnections,the Computer Smart III FASTusesindividualenergymetersforeach
stage�
The Reconnection time, Trec,istheshortestpossibletimebetweendisconnectingastage
andreconnectingit�Thistimeisnecessaryforthecapacitortodischargeenoughsothat,when
itisreconnected,itdoesnotcauseovercurrentsinthesystem�
Both TonandTrechavedifferenttimebasesfortheComputer SMART III (inseconds)andfor
the Computer SMART III FAST (innetworkcycles)�
4�1�7 THD and harmonics
Non-linearloads,suchasthoseinrectifiers,inverters,variablespeeddrivers,furnaces,etc�,
absorbnon-sinusoidalperiodiccurrentsfromthemains�Thesecurrentsaremadeupofafun-
damentalcomponentwithafrequencyof50or60Hz,plusaseriesofoverlappingcurrentswith
frequenciesthataremultiplesofthefundamentalfrequency;thesearedefinedasharmonics�
Theresultisadeformationofthecurrentand,thus,ofthevoltage,whichleadstoaseriesof
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Computer SMART III FAST
Instruction Manual