ABB RELION REF615R, Technical Manual

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A070420-ANSI V1 EN
Figure 295: Drop-off period is shorter than the set Reset delay time
When the drop-off period is shorter than the set Reset delay time , as described in Figure
295 , the input signal for the definite timer (here: timer input) is active, provided that the
current is above the set Pickup value . The input signal is inactive when the current is below
the set Pickup value and the set hysteresis region. The timer input rises when a fault current
is detected. The definite timer activates the
PICKUP
output and the operation timer starts
elapsing. The reset (drop-off) timer starts when the timer input falls, that is, the fault
disappears. Another fault situation occurs before the reset (drop-off) timer has elapsed.
This causes the activation of the
TRIP
output, since the operation timer already has
elapsed.
1MRS240050-IB C
Section 12
General function block features
REF615R 569
Technical Manual