ABB RELION 670 Series Technical Manual page 600

Section 8
Current protection
ReclsLevTheta represents the Theta value below which is safe again to re-connect the tripped
generator to the network.
The output signal PICKUP will reset if the measured current falls below reset level or if BLOCK
signal is set to one. However the Theta value is stored in the IED memory and it starts to decay
slowly following a linear reset characteristic defined by the parameter
tReset actually defines the rest time for Theta from value 100% to zero. Note that if an overload
condition happens again, the last theta value is used as a starting point for the calculation. Thus
the rotor winding will be properly protected against varying current levels.
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1MRK 502 066-UUS B
tReset. The parameter
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