ABB REB670 Applications Manual page 169

1MRK 505 337-UUS -
Application manual
time delay. Thus, if only the inverse time delay is required, it is important
to set the definite time delay for that stage to zero.
The parameters for Four step phase overcurrent protection 3-phase output OC4PTOC
(51/67) are set via the local HMI or PCM600.
The following settings can be done for OC4PTOC (51/67).
GlobalBaseSel: Selects the global base value group used by the function to define (IBase),
(VBase) and (SBase).
MeasType: Selection of discrete Fourier filtered (DFT) or true RMS filtered (RMS)
signals. RMS is used when the harmonic contents are to be considered, for example in
applications with shunt capacitors.
Operation: The protection can be set to Disabled or Enabled
AngleRCA: Protection characteristic angle set in degrees. If the angle of the fault loop
current has the angle RCA the direction to fault is forward.
AngleROA: Angle value, given in degrees, to define the angle sector of the directional
function, see figure 77.
PUMinOpPhSel: Minimum current setting level for releasing the directional start signals
in % of IBase. This setting should be less than the lowest step setting. Default setting is
7%.
NumPhSel: Number of phases, with high current, required for operation. The setting
possibilities are: Not used,1 out of 3, 2 out of 3 and 3 out of 3. Default setting is 1 out of 3.
2ndHarmStab: Operate level of 2nd harmonic current restrain set in % of the fundamental
current. The setting range is 5 - 100% in steps of 1%. Default setting is 20%.
Section 7
Current protection
163