IGS-NT-BC, SW Version 1.2.0, ©ComAp – January 2019
IGS-NT-BC-1.2.0 Reference Guide.PDF
This setpoint adjust the delay for generator fast overcurrent protection. The limit
for the protection is adjusted by the setpoint Ishort.
NOTE:
Although the resolution of this setpoint is 0.01s, in fact the adjusted delay is
rounded to the next higher multiple of the period of the generator voltage. The
period is either 0.02s for 50Hz systems or 0.0166s for 60Hz systems. E.g. if the
delay is set to 0.03s at 50Hz system the real delay will be 0.04s.
This setpoint adjusts the reaction time of the IDMT overcurrent protection if the
overcurrent level is 200% of the nominal current.
The reaction time of the IDMT overcurrent protection is not fixed; it depends on
how much is the actual current above the limit (nominal). The higher is the
overcurrent the shorter the reaction time will be.
EXAMPLE OF IDMT OVERCURRENT PROTECTION CURVE
NOTE: