ABB REB670 Applications Manual page 139

1MRK 505 337-UUS -
Application manual
busbar station with sectionalizer or bus-section breaker, but are characterized by very
limited number of feeder bays connected to the station (normally only two OHL and two
transformers).
01
52
52
ZA
52
03
ANSI06000121 V1 EN
Figure 56: Example of H-type station
The requirement for the busbar protection scheme for this type of station may differ from
utility to utility. It is possible to apply just one overall differential zone, which protects
both busbar sections. However, at an internal fault on any of the two buses all feeder
circuit breakers have to be tripped, which will cause loss of supply to all loads connected
to this station. Some utilities prefer to have two differential zones, one for each bus
section.
The most common setups for this type of station are given in the following table.
Differential protection
02
52
ZB
52
04
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