4. Application
The feeder protection IED REF615 can be
supplied either with directional or nondi-
rectional earth-fault protection. Directional
earth-fault protection is mainly used in
isolated or compensated networks, whereas
non-directional earth-fault protection is in-
tended for directly or low impedance earthed
networks.
The standard configurations A and B offer di-
rectional earth-fault protection, if the outgo-
ing feeder includes phase current transform-
ers, a core-balance current transformer and
residual voltage measurement. The residual
current calculated from the phase currents
can be used for double (cross country) earth-
fault protection. The IED further features
transient/intermittent earth-fault protection.
The standard configurations C and D offer
non-directional earth-fault protection for out-
going feeders including phase current trans-
Fig. 5 Substation O/C and E/F protection using the standard configuration A or B with
relevant options. In the incoming feeder bay, the protection functions not used are
uncoloured and indicated with a dashed block outline. The IEDs are equipped with
optional arc protection functions, enabling fast and selective arc protection throughout
the switchgear.
To Next Page
Loading...
Need help?
General
