Setting Guidelines; Settings For Each Step (X = 1, 2, 3 And 4) - ABB Relion 670 Series Applications Manual

1MRK 511 358-UUS A
7.4.3

Setting guidelines

The parameters for the four step residual overcurrent protection are set via the local HMI or
PCM600. The following settings can be done for the function.
GlobalBaseSel : Selects the global base value group used by the function to define ( IBase ), ( VBase )
SBase ).
and (
SeqTypeUPol : This is used to select the type of voltage polarising quantity i.e. Zero seq or Neg seq
for direction detection.
SeqTypeIPol : This is used to select the type of current polarising quantity i.e. Zero seq or Neg seq
for direction detection.
SeqTypeIDir : This is used to select the type of operating current quantity i.e. Zero seq or Neg seq
for direction detection.
7.4.3.1

Settings for each step (x = 1, 2, 3 and 4)

Operation : Sets the protection to Enabled or Disabled .
DirModeSelx : The directional mode of step x . Possible settings are Disabled / Non-directional /
Forward / Reverse .
Characteristx : Selection of time characteristic for step x . Definite time delay and different types of
inverse time characteristics are available.
Inverse time characteristic enables fast fault clearance of high current faults at the same time as
selectivity to other inverse time phase overcurrent protections can be assured. This is mainly used
in radial fed networks but can also be used in meshed networks. In meshed networks, the settings
must be based on network fault calculations.
To assure selectivity between different protections, in the radial network, there has to be a
minimum time difference Dt between the time delays of two protections. To determine the
shortest possible time difference, the operation time of protections, breaker opening time and
protection resetting time must be known. These time delays can vary significantly between
different protective equipment. The following time delays can be estimated:
Protection trip time:
Protection resetting time:
Breaker opening time:
The different characteristics are described in the technical reference manual.
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.
15-60 ms
15-60 ms
20-120 ms
Section 7
Current protection
IP14988-1 v1
M15282-3 v12
M15282-9 v12.1.1
139