GE GEK-106273L Instruction Manual page 153

ANNEX 1 THERMAL IMAGE UNIT
ambient, it different depending on if the machine is stopped or if it is spinning. To detect this stopped motor or
generator (or in general, protected element disconnected), MIF relay uses an internal current level detector, fixed to
15% In. If the current flowing through the element is lower than this value, the relay will consider that the element is
disconnected and will use in its algorithms and equations a different "Cooling" time constant τ2. This time constant is
a setting in the relay, and its range is from 1 to 6 times the heating time constant τ1. If the current is greater than
15% In, the element will be considered to be connected (spinning), and then, the cooling time constant will be τ1.
11-6 MIF Digital Feeder Protection GEK-106273L