Vt Assignment; Enabling Tripping Commands; Overcurrent Release Of The Trip Command - ABB REB500 Technical Manual

1MRK 505 350-UEN
6.1.2
6.1.2.1
6.1.2.2
6.2
6.2.1
Technical Manual
Distributed busbar protection REB500

VT assignment

Figure 23 VT assignment
Assignment to a feeder or a bus-tie breaker
Figure 23 shows that VT T5 is assigned to feeder 3 and therefore measures the
feeder voltage.
Assignment to a protection zone
Figure 23 shows that VT T5 (2.2) measures the voltage at bus-tie breaker 2.1. Both
are integrated in the hardware of bay unit 2, but VT T5 (2.2) measures the voltage
on the busbars in protection zone I.
The same applies to protection zone II, i.e. VT T5 (4.4) is connected at bus-tie
breaker 4.1. It is integrated in the hardware of bay unit 4 but measures the voltage
on the busbars in protection zone II.

Enabling tripping commands

Overcurrent release of the trip command

It is occasionally specified that when tripping a busbar zone only those feeders are
tripped which are actually conducting fault current (active feeders), while those
which are not (passive feeders) are left connected. This logic can be achieved by
configuring an additional low current check feature per bay unit, which only
enables tripping of feeders that are actually conducting current.
Section 6
Additional functions
55