ABB RELION 620 Series Technical Manual page 838

Section 12
General function block features
832
GUID-9BFD6DC5-08B5-4755-A899-DF5ED26E75F6 V1 EN
Figure 426: Example of how the inverse time characteristic is leveled out with
currents over 50 x In and the Setting Start value setting "2.5 x In". (the
IDMT Sat point setting is set to maximum and the Minimum operate time
setting is set to minimum).
The grey zone in Figure 426
is outside the guaranteed measuring range. Also, the maximum measured current of 50 x
In gives the leveling-out point 50/2.5 = 20 x I/I>.
shows the behavior of the curve in case the measured current
1MAC504801-IB E
620 series ANSI
Technical Manual