Setting Guidelines - Hitachi Relion 670 Series Applications Manual

1MRK511407-UUS Rev. N
8.1.4

Setting guidelines

The parameters for the directional phase overcurrent protection, four steps OC4PTOC (51/67) are set via
the local HMI or PCM600.
The following settings can be done for OC4PTOC (51/67).
Common base IED values for the primary current (IBase), primary voltage (VBase) and primary power
(SBase) are set in global base values for settings function GBASVAL.
GlobalBaseSel: Selects the global base value group used by the function to define IBase, VBase and
SBase. Note that this function will only use IBase .
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 Enabled or Disabled.
AngleRCA: Protection characteristic angle set in degrees. If the angle of the fault loop current has the
angle RCA, the direction to the fault is forward.
AngleROA: Angle value, given in degrees, to define the angle sector of the directional function, shown in
Figure 53.
NumPhSel: Number of phases, with high current, required for operation. The setting possibilities are: 1
out of 3, 2 out of 3 and 3 out of 3. The default setting is 1 out of 3.
PUMinOpPhSel: Minimum current setting level for releasing the directional start signals in % of IB. This
setting should be less than the lowest step setting. The default setting is 7% of IB.
2ndHarmStab: Operate level of 2nd harmonic current restrain set in % of the fundamental current. The
setting range is 5 - 100% in steps of 1%. The default setting is 20%.
Phasor measurement unit RES670
Application manual
When inverse time overcurrent characteristic is selected, the trip time of the stage will be the
sum of the inverse time delay and the set definite 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.
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Section 8
Current protection
IP14982-1 v1
M12982-4 v15
111