Sepam - HV/MV Protection and control units (ENG) - Trinet

Motor/generator differential protectionANSI codefunction n°87M - 87GF621Equipmentc 2 current generatorsc 2 ammetersc 2 adapters for ECA modulesc "protection function" documentationc calculatorWiringc diagrams B1 and B13c protective relays: F621/4Testc read the section entitled measurement and testingmethodThis function operates on the 3 phases individuallyand may be tested with single-phase, one phaseat a time.The test calls for the use of two current injection units.In order for the measurements to be accurate,the two currents must be in phase.c status parameter settingv check the microswitches on the two ECM or ECAProcedurec Protection parameter setting: motor diff or gene diffv set Is as a % of In to the desired value (5% to 50% of In)v disable the following protections (2) :O/Cx, E/Fx (if sum of 3 CTs is used), thermal overload, unbalance, Start Hour,LR/ESttesting of operationv determine the operating point to be tested, i.e :choose the value of It/Inchoose the value of Is/Inv read in the chart which follows the minimum value of Id/In that trips theprotection, with Id/In ≥ 1.2 Is/Inv preset the injections:v inject the two currents IA and Id at the same time according to diagram B13,with IA = It - Id 2v check on F621/4 that the function has picked upv cut off the injectionsv press the "reset" button (1) on Sepam 2000 to earase the messages and make therelay drop out again.c examplev testing the protection for a through- current of In and an Is setting of 20% of Inv use the chart to read:for It/In = 1 and Is/In = 0.2read the value of Id/In: 0.2669Preset Is = 0.84 In et Id = 0.32 Inv inject the 2 currents at the same timev the relay picks upv press reset (1) on Sepam 2000 to erase the message and make the relay drop outagain.Testing of tripping timev wire according to diagram B1; use a single current generator (I' = 0)v given I = 1,2 Inv preset I1 to 40 A, i.e. 1 A in the secondary circuitv set the chronometer to zerov start injection and the chronometer at the same timev after the chronometer is stopped by the Sepam 2000 relay, read the time(about 40 ms)(1)this function may only be activated if your program logichas been customized.(2)remember to reactivate the protections at the end of testing.X = number of the protective relay.1/50Sepam 2000 - Testing