Table 14:Typical solutions for single busbar arrangementVersion of REB670 IED Numbers of feeders perbusbarNumber of REB670 IEDsrequired for the scheme3PH; 2-zones, 4-bays BBP (A20) 4 13PH; 2-zones, 8-bays BBP (A31) 8 11Ph; 2-zones, 12-bays BBP (B20) 12 31Ph; 2-zones, 12-bays BBP (B21) 12 31Ph; 2-zones, 24-bays BBP (B31) 24 3Please note that the above Table 14 is given for the preconfigured versions of REB670which do not contain any VT inputs.6.1.4.3 Single busbar arrangements with sectionalizer M6642-3 v5This arrangement is very similar to the single busbar arrangement. The sectionalizerallows the operator to split the station into two separate buses. However, switching ofthe sectionalizing disconnector has to be done without any load. This means that one ofthe two busbars has to be de-energized before any opening or closing of thesectionalizer.For this case the protection scheme must have two differential zones, which can beeither split to work independently from each other or switched to one overalldifferential zone when sectionalizing disconnector is closed. Nevertheless, whensectionalizer is closed, for internal fault on any of the two buses all feeder circuitbreakers have to be tripped, which causes loss of supply to all loads connected to thisstation.189ZA ZBANSI11000238-1-en.vsd152 152 152 152 152 152152ANSI11000238 V1 EN-USFigure 55: Example of two single busbar sections with bus-sectionalizingdisconnector and eight feeder bays per each busbar section1MRK 505 370-UUS A Section 6Differential protectionBusbar protection REB670 2.2 ANSI 137Application manual
