Centralized Trip Unit; Decentralized Trip Arrangement - ABB REB670 Applications Manual

1MRK 505 337-UUS -
6.1.3.14
6.1.3.15
Application manual
IEC06000227 V1 EN
Figure 52: Principal trip arrangement via GOOSE between three one-phase IEDs

Centralized trip unit

Tripping is performed directly from the IED contacts, which then activate an auxiliary trip
unit, which multiplies the number of required trip contacts. Separate potential free
contacts are provided for each bay and are supplied by the bay auxiliary voltage and will
activate the trip coil of each bay circuit breaker at operation. This tripping setup is suitable
when no individual circuit breaker failure IEDs or lock-out of individual bay CB closing
coils is required. A suitable external trip unit consists of a combination of RXMS1/RXMH
2 alternatively AR/MG6 when heavy duty contacts are required and only RXMS 1/AR
relays when medium duty contacts are sufficient.

Decentralized trip arrangement

Tripping is performed directly from the IED contacts, which then activate dedicated
auxiliary trip unit per bay. This individual auxiliary trip unit can be mounted either in the
busbar protection cubicle or in the individual bay cubicles. This tripping setup is suitable
when individual circuit breaker failure relays exist in all bays. A suitable external trip unit
consists of a combination of RXMS1/RXMH 2 alternatively AR/MG6 when heavy duty
ZoneA Trip
IED 670
ZoneB Trip
50 ms
Ext ZoneA Trip
IED 670
50 ms
Ext ZoneB Trip
50 ms
Ext ZoneA Trip
IED 670
50 ms
Ext ZoneB Trip
t
Section 6
Differential protection
GOOSE for ZoneA
GOOSE for ZoneB
Switch
en06000227.vsd
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