f-Protection Module – Frequency [81O/U, 78, 81R]
f-Protection Module – Frequency [81O/U, 78, 81R]
Available stages: 6
f[1] ,f[2] ,f[3] ,f[4] ,f[5] ,f[6]
All frequency protective elements
f[1]
to
f[6]
are identically structured.
The frequency is calculated as the average of the measured values of the
three phase frequencies. Only valid measured frequency values are taken
into account. If a phase voltage is no longer measurable, this phase will be
excluded from the calculation of the average value.
EN MRU4 10/09
Page 253
