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

Ii (% Ib) K10 99.9515 54.5020 35.4425 25.3830 19.3233.33 16.5135 15.3440 12.5645 10.5350 9.0055 8.2157.5 7.8460 7.5565 7.0070 6.5275 6.1180 5.7485 5.4290 5.1395 4.87100 4.64110 4.24120 3.90130 3.61140 3.37150 3.15160 2.96170 2.80180 2.65190 2.52200 2.40Ii (% Ib) K210 2.29220 2.14230 2.10240 2.01250 1.94260 1.86270 1.80280 1.74290 1.68300 1.627310 1.577320 1.53330 1.485340 1.444350 1.404360 1.367370 1.332380 1.298390 1.267400 1.236410 1.18420 1.167430 1.154440 1.13450 1.105460 1.082470 1.06480 1.04490 1.02≥ 500 1Testing of IDMT set points and time delayThe set point and time delay are IDMT and correspond to the curve and chartcoordinates (see in appendix).tTIs5Ibc protection parameter setting: Unbalancev select the IDMT curvev set Is as a % of Ibv set Tv disable the O/C and E/F X protections (if sum of 3 CTs is used)c checking of tripping timev preset the injection i > 1.732 Is or 3 Is (according to the injection wiring diagram)v stop the injection and reset the chronometer to zerov press reset if required (1)v start up injection and the chronometer at the same timev check the injection value on the ammeter (stability)v Sepam's 2000 output relay stops the chronometerv read the t value measured by the chronometerv check the measurement and the I TRIP (1) values on the pocket terminalv stop the injectionv press reset (1) on Sepam 2000 to erase the messages and reset the output relayexamplestatus In = 400 A Ib = 320 AFinding settingsFor a given unbalance value of 80A that is supposed to trip in 5 s, the IDMT curvedetermined by T should be selected using the chart which gives K in relation to Ii(%Ib).In the example above, Ii = 25% Ib, hence k = 25.38T should be set to 5/25.38 = 197 msT = 200 ms will be selectedSetting Is ≤ 25% of Ib, T = 200 msInjectionIn accordance with the injection diagram used:- diagram B1 (2CT): i = 80 x 1.732 = 138 A- diagram B1 (3CT): i = 80 x 3 = 240 A- diagram B9 (2 or 3CT): i = 138 AThe operating time measured should be:t = 25.38 x 0.2 = 5 sI(1)this function may only be activated if your program logichas been customized.X = number of the protective relay.Sepam 2000 - Testing1/27