3
Directional Earth-fault Relay
Product Guide
SPAS 120 C
Features
� Two-stage directional earth-fault relay for
distribution networks
� Directional low-set earth-fault stage with
definite time characteristic
� Directional high-set earth-fault stage with
instantaneous operation or definite time
characteristic
� Operation direction of the high-set earth- fault stage either the same as that of the low-set stage, or the opposite
� Output relay functions to be freely config-
ured by the user
� Flexible adaptation of the relay to different
applications
� Manual selection or remote control of the
operation characteristic I0sin� or I0cos�
� Digital display of settings, measured quan-
tities, recorded fault values, etc.
� Extensive two-way data communication via
fibre-optic serial bus
� Continuous self-supervision of hardware
and software including auto-diagnosis
� Powerful software support for parameter-
ization and supervision of the relay
Application
The directional earth-fault relay SPAS 120 C
is designed to be used for selective feeder
earth-fault protection in isolated neutral and
impedance earthed networks. The relay is
especially useful in networks, where the oper-
ation characteristic of the earth-fault relay
must be remotely controllable.
The directional earth-fault relay can also be used for the earth-fault protection of power generators and large motors. |