GE Industrial Solutions Entellisys System User Manual - Manual (Page 101)

PT Throw-Over 101
7
In Topology 3, all three topology circuit breakers are closed, so the sources at M1 and M2 are
operating in parallel. In this case, the feeder circuit breakers can use either circuit breaker as a
voltage source. For simplicity, the sources are defined exactly as they are for Topology 1.
The tie circuit breaker T1 is a special case, because it is a member of both zones. The way
Entellisys handles this case, for the purposes of PT Throwover only, is to treat it as a member of
the lowest-numbered zone of which it is a member. In the example above, T1 is treated as a
member of Zone 1 only.
Table 7-1 PT Throwover matrix
Circuit Breaker Names PT Source
Topology 0 PT Source
Topology 1 PT Source
Topology 3 PT Source
Topology 4
M1 M1 M1 M1 M1
M2 M2 M2 M2 M2
T1 M1 M1 M2 M1
FL1 M1 M1 M2 M1
FL2 M1 M1 M2 M1
FR1 M2 M2 M1 M2
FR2 M2 M2 M1 M2