Operation Manual 37107F
MFR 3 - Multi Function Relay
© Woodward
Page 105/165
Earth Fault Monitoring
Calculation of the ground current:
The measuring of the ground current is based on the calculation of the vectoral sum of the three phase currents.
To ensure that the ground fault protection operates properly, the configured ground currents should be a mini-
mum of 10% of the current transformer’s rating.
Parameter
147
Earth fault
monitoring ON
Ground fault monitoring
ON/OFF
ON
................ Ground fault monitoring is enabled. The subsequent screens of this
function are displayed.
OFF
.............. Ground fault monitoring is not performed. The subsequent screens of
this function are not displayed.
Parameter
148
Earth fault
response v. 000%
Threshold ground current limit
5 to 100 %
If the value of the ground current exceeds the entered percentage, the unit issues an
alarm. In an additional relay is configured in the relay manager the alarm is also
transmitted to this relay.
Parameter
149
Earth fault
delay 00,00s
Earth fault delay
0.02 to 99.98 s
The ground fault monitoring threshold limit must be exceeded, without interrup-
tion, for the time period configured here before the configured relay will be ener-
gized.
