Instruction manual –AQ F210 Feeder Protection IED
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4.2.3.4
O
PERATING TIME CHARACTERISTICS FOR TRIP AND RESET
The operating timers’ behavior of the function can be set for trip signal and also for the
release of the function in case the pick-up element is reset before the trip time has been
reached. There are three basic operating modes available for the function. Instant operation
gives the trip signal with no additional time delay simultaneously with start signal. Definite
time operation (DT) will give trip signal with user given time delay regardless of the
measured current as long as the current is above the Iset value and thus pick-up element
is active (independent time characteristics). Inverse definite minimum time (IDMT) will give
the trip signal in time which is in relation of the set pick-up current Iset and measured current
Im (dependent time characteristics). For the IDMT operation is available IEC and
IEEE/ANSI standard characteristics as well as user settable parameters.
In the following table are presented the setting parameters for the function time
characteristics.