This type of busbar arrangement can be very easily protected. The most common setupsfor this type of station are described in the following table.Table 13: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 13 is given for the preconfigured versions of REB670which do not contain any VT inputs.6.1.4.3 Single busbar arrangements with sectionalizerThis arrangement is very similar to the single busbar arrangement. The sectionalizerallows the operator to split the station into two separate buses. However, switching of thesectionalizing disconnector has to be done without any load. This means that one of thetwo busbars has to be de-energized before any opening or closing of the sectionalizer.For this case the protection scheme must have two differential zones, which can be eithersplit to work independently from each other or switched to one overall differential zonewhen sectionalizing disconnector is closed. Nevertheless, when sectionalizer is closed,for internal fault on any of the two buses all feeder circuit breakers have to be tripped,which causes loss of supply to all loads connected to this station.Section 6 1MRK 505 337-UUS -Differential protection130Application manual
