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

Hot curves:t/T1 = f(OL, I/Ib)The following charts give the numerical values of thehot curves.Example of chart useFor an operation set point OL of 115% with a time constant T1 of 15 mn,what is the operation time when hot at 2.6 Ib?Using the hot curve chart:c read the value t/T1 = 0. 0264 at the intersection of row OL = 115 and columnI/Ib = 2.6c calculate the operation timet = 0.0264 x T1i.e. t = 0.0264 x 15 x 60 = 23.7 sI/Ib 1.00 1.05 1.10 1.15 1.20 1.25 1.30 1.35 1.40 1.45 1.50 1.55 1.60 1.65 1.70 1.75 1.80OL (%)105 0.6690 0.2719 0.1685 0.1206 0.0931 0.0752 0.0627 0.0535 0.0464 0.0408 0.0363 0.0326 0.0295 0.0268 0.0245 0.0226110 3.7136 0.6466 0.3712 0.2578 0.1957 0.1566 0.1296 0.1100 0.0951 0.0834 0.0740 0.0662 0.0598 0.0544 0.0497 0.0457115 1.2528 0.6257 0.4169 0.3102 0.2451 0.2013 0.1699 0.1462 0.1278 0.1131 0.1011 0.0911 0.0827 0.0755 0.0693120 3.0445 0.9680 0.6061 0.4394 0.3423 0.2786 0.2336 0.2002 0.1744 0.1539 0.1372 0.1234 0.1118 0.1020 0.0935125 1.4925 0.8398 0.5878 0.4499 0.3623 0.3017 0.2572 0.2231 0.1963 0.1747 0.1568 0.1419 0.1292 0.1183130 2.6626 1.1451 0.7621 0.5705 0.4537 0.3747 0.3176 0.2744 0.2407 0.2136 0.1914 0.1728 0.1572 0.1438135 1.5870 0.9734 0.7077 0.5543 0.4535 0.3819 0.3285 0.2871 0.2541 0.2271 0.2048 0.1860 0.1699140 2.3979 1.2417 0.8668 0.6662 0.5390 0.4507 0.3857 0.3358 0.2963 0.2643 0.2378 0.2156 0.1967145 1.6094 1.0561 0.7921 0.6325 0.5245 0.4463 0.3869 0.3403 0.3028 0.2719 0.2461 0.2243150 2.1972 1.2897 0.9362 0.7357 0.6042 0.5108 0.4408 0.3864 0.3429 0.3073 0.2776 0.2526155 3.8067 1.5950 1.1047 0.8508 0.6909 0.5798 0.4978 0.4347 0.3846 0.3439 0.3102 0.2817160 2.0369 1.3074 0.9808 0.7857 0.6539 0.5583 0.4855 0.4282 0.3819 0.3438 0.3118165 2.8478 1.5620 1.1304 0.8905 0.7340 0.6226 0.5390 0.4738 0.4215 0.3786 0.3427170 1.9042 1.3063 1.0076 0.8210 0.6914 0.5955 0.5215 0.4626 0.4146 0.3747175 2.4288 1.5198 1.1403 0.9163 0.7652 0.6554 0.5717 0.5055 0.4520 0.4077180 3.5988 1.7918 1.2933 1.0217 0.8449 0.7191 0.6244 0.5504 0.4908 0.4418185 2.1665 1.4739 1.1394 0.9316 0.7872 0.6802 0.5974 0.5312 0.4772190 2.7726 1.6946 1.2730 1.0264 0.8602 0.7392 0.6466 0.5733 0.5138195 4.5643 1.9782 1.4271 1.1312 0.9390 0.8019 0.6985 0.6173 0.5518200 2.3755 1.6094 1.2483 1.0245 0.8688 0.7531 0.6633 0.5914Sepam 2000 - Testing1/23