VAMP 52 - Page 185

Technical description 7 Application 7.1 Substation feeder protection
VM50.EN004 VAMP 24h support phone +358 (0)20 753 3264
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VAMP 50
Overcurrent and Earth/fault Relay
Power
Error
Alarm
Trip
VAMP 50
Overcurrent and Earth/fault Relay
Power
Error
Alarm
Trip
Figure 7.1-2 VAMP 52 used in substation feeder protection in compensated
network
For the directional function of earth fault function, the status
information (on/off) of the Petersen coil is routed to one of the
digital inputs of the feeder device so that either I
0sin

or I
0cos

function is obtained.
The function I
0sin

is used in isolated networks, and the
function I
0cos

is used in resistance or resonant earthed
networks.