Application Guide - NP900 Series
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A996A
common event buffer from each of the three output signal. In instant operating mode the
function outputs START and TRIP events simultaneously with equivalent time stamp.
Time stamp resolution is 1ms. Function provides also cumulative counters for START,
TRIP and BLOCKED events.
In the following figure is presented the simplified function block diagram of the NEF
function.
Figure 3.2.3-35 Simplified function block diagram of the NEF function.
3.2.3.1
M
EASURED INPUT VALUES
Function block uses analog current measurement values. Function block always utilizes
peak-to-peak measurement from samples and by user selection the monitored magnitude
can be either fundamental frequency RMS values, True RMS values from the whole
harmonic specter of 32 components or peak to peak values. -20ms averaged value of the
selected magnitude is used for pre-fault data registering.
