For some protection applications there can be a need to change the current
operating level for some time. Therefore there is a possibility to give a setting of a
multiplication factor IxMult to the negative sequence current pick-up level. This
multiplication factor is activated from a binary input signal ENMULTx to the
function.
7.3.3 Setting guidelines
GUID-460D6C58-598C-421E-AA9E-FD240210A6CC v3
The parameters for Four step negative sequence overcurrent protection NS4PTOC
are set via the local HMI or Protection and Control Manager (PCM600).
The following settings can be done for the four step negative sequence overcurrent
protection:
Operation: Sets the protection to On or Off.
Common base IED values for the primary current (IBase), primary voltage (UBase)
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, UBase and SBase as applicable.
GUID-F7AA2194-4D1C-4475-8853-C7D064912614 v4
When inverse time overcurrent characteristic is selected, the
operate 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.
7.3.3.1 Settings for each step
GUID-CFB327EF-C5C4-44B5-AB4B-9C2916355FC5 v5
x means step 1, 2, 3 and 4.
DirModeSelx: The directional mode of step x. Possible settings are off/
nondirectional/forward/reverse.
Characteristx: Selection of time characteristic for step x. Definite time delay and
different types of inverse time characteristics are available.
Table 16: Inverse time characteristics
Curve name
ANSI Extremely Inverse
ANSI Very Inverse
ANSI Normal Inverse
Table continues on next page
1MRK 505 388-UEN B Section 7
Current protection
Busbar protection REB650 2.2 IEC 113
Application manual