ABB Relion REB500, Руководство по вводу в эксплуатацию

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1MRK 505 351-UEN
Section 2
Commissioning
Commissioning Manual 13
Distributed busbar protection REB500
In case of a bus-tie breaker equipped with two sets of CTs, make sure that the set of
CTs assigned to the busbar section under test is checked. The simplest way of
ensuring this is to short-circuit the CTs belonging to the section not under test
directly at the CTs or as close as possible to them.
Figure 3 Through-fault stability by primary injection (bus-tie breaker)
The feeder currents and the differential current can be read using HMI500.
The comparison with the reference feeder has to be conducted for
phase
and neutral currents for protection schemes that evaluate the
neutral current.
2.2.8.2 Checking through-fault stability with de-energized busbars
Where protection stability cannot be tested before the busbar is energized or in the
case of an extension to an existing system, it has to be tested using load current.
For this test, either tripping by the protection has to be blocked or
the tripping circuits have to be interrupted
before the currents are
applied to the protection.
Reference feeder
Primary
injection
test set
Short- circuit CTs
I
II