ROADir is Relay Operating Angle. ROADir is identifying a window around the reference
direction in order to detect directionality. ROADir is set in degrees. For angles differing
more than ROADir from RCADir the function is blocked. The setting can be used to
prevent unwanted operation for non-faulted feeders, with large capacitive ground fault
current contributions, due to CT phase angle error.
INCosPhiPU is the pickup current level for the directional function when OpModeSel is
set 3I0Cosfi. The setting is given in % of IBase. The setting should be based on calculation
of the active or capacitive ground fault current at required sensitivity of the protection.
SN_PU is the pickup power level for the directional function when OpModeSel is set
3I03V0Cosfi. The setting is given in % of SBase. The setting should be based on
calculation of the active or capacitive ground fault residual power at required sensitivity
of the protection.
The input transformer for the Sensitive directional residual over current and power
protection function has the same short circuit capacity as the phase current transformers.
Hence, there is no specific requirement for the external CT core, i.e. any CT core can be
used.
If the time delay for residual power is chosen the delay time is dependent on two setting
parameters. SRef is the reference residual power, given in % of SBase. TDSN is the time
multiplier. The time delay will follow the following expression:
inv
0 0
TDSN Sref
t
3I 3V cos (measured)
×
=
× × j
EQUATION2030-ANSI V1 EN (Equation 481)
INDirPU is the pickup current level for the directional function when OpModeSel is set
3I0 and fi. The setting is given in % of IBase. The setting should be based on calculation
of the ground fault current at required sensitivity of the protection.
OpINNonDir is set Enabled to activate the non-directional residual current protection.
INNonDirPU is the pickup current level for the non-directional function. The setting is
given in % of IBase. This function can be used for detection and clearance of cross-country
faults in a shorter time than for the directional function. The current setting should be
larger than the maximum single-phase residual current on the protected line.
TimeChar is the selection of time delay characteristic for the non-directional residual
current protection. Definite time delay and different types of inverse time characteristics
are available:
Section 9 1MRK 506 369-UUS -
Current protection
538 Line distance protection REL670 2.2 ANSI
Application manual
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