ABB Relion REC670 Applications Manual page 96

Section 6
Differential protection
in fault current to allow the use of only the AC components of the fault current in the above
calculations.
The voltage dependent resistor (Metrosil) characteristic is shown in Figure 38.
Series resistor thermal capacity
The series resistor is dimensioned for 200 W. Preferable the
always be lower than 200 W to allow continuous activation during testing. If this value is
exceeded, testing should be done with a transient faults.
90
1MRK 511 358-UEN A
U>Trip 2 /SeriesResistor should
Application manual
SEMOD54734-336 v6