Ctdim is a software tool for current transformer ct and voltage potential. For engineering calculation purposes it is necessary to define only one phasor in. When used in providing transformer differential protection, these c. Ct winding arrangements, and software phase compensation are to be made. Itl is a uk leading low voltage transformers manufacturer. For engineering calculation purposes it is necessary to define only. Some particular relays can even compensate online for ltc movement 3, 4 and. Typical voltage and current reference direction for a power transformer power transformer differential protection scheme with interposing cts. Professionals with experience in transformer assemblies use the computer program to calculate the number of coils and wire thickness. Pdf differential protection for standard power transformers has. Current transformer calculation extreme electronics. Interposing current transformer is defined as the one in which there is a piece of equipment with a ratio whose selection can be done by the user in order to do the achievement of the balance. The standard current transformer secondary winding is rated at 5a as per ansi standards. Chk gridsense, interposing ct,chk,gridsense chk power quality.
Calculation and analysis of transformer inrush current based on parameters of transformer and operating conditions article pdf available march 2011 with 16,021 reads how we. Referring to the figure, the interposing current transformers icts have. Single phase transformer fullload current amps kva. Cp4 series encapsulated interposing current transformer. The main fuction of an interposing ct is to balance the current supplied to the relay or others where threre would otherwise be an imbalance due to the ratios of the main cts. Current transformer calculations enter values in white, ct values are calculated automatically. It is important to note, however, that these solutions are best only for those experts who have knowledge and experience with assembly transformers. Bartype current transformer this type of current transformer uses the actual cable or busbar of the main circuit as the primary winding, which is equivalent to a single turn. Ts are also used to correct the phase shift, which may result due to particular method of connection used for the.
Three good examples of the application of modern relays to. With modern numerical transformer differential relays all above compensations are provided in the relay software. Interposing cts also provide a convenient method of establishing a delta connection for the elimination of zero sequence currents where this is necessary. What is an interposing current transformer, and why is it. They are fully insulated from the high operating voltage of the system and are usually bolted to the current carrying device.
Ctdim current and voltage transformer selection, dimensioning. Interposing cts are equipment with a ratio that can be selected by the user to achieve the balance required. Are you looking for the best transformer calculator software for your next project. Current transformer basics and the current transformer. Pdf easy method for testing transformer differential relays. The main purpose of a current transformer is to translate the primary current in a high voltage power system to a signal level that can be handled by delicate electromechanical or electronic devices. Auto analyze windings connection to create desired vector group and define best choose for position of end leads of windings. Interposing current transformer interposing types can be used to modify the secondary current from an existing line ct. Csh30 interposing ring current transformer ct installation sheet, instruction bulletin ansi, 63230216252a1, may 2007 published date. The foremost interface device between the power system and the protective relaying is the ubiquitous current transformer. Sample calculationfordifferentialrelays slideshare. The transformer calculator uses the following formulas.1299 1672 585 339 425 988 1406 1138 441 1519 1678 1431 14 60 1682 502 1374 172 1408 1295 335 759 1098 120 1041 1558 807 1233 415 929 1538 178 549 745 1234 1554 101 687 478 671 631 1333 1284 579 1199 625 295 963