scheider electric MiCOM P746, Technical Manual

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Symbols and Glossary P746/EN SG/F21
MiCOM P746 (SG) 14-
5
SG
Symbols Explanation
MICS
Model Implementation Conformance Specification:
Defines the IEC 61850 data model implemented in an IED.
MMS Manufacturing Message Specification:
A protocol used to transport the data of IEC 61850 across an Ethernet network.
N Indication of “Neutral” involvement in a fault:
i.e. a ground (earth) fault.
N/A Not applicable.
N/C A normally closed or “break” contact:
Often called a “form B” contact.
N/O A normally open or “make” contact:
Often called a “form A” contact.
NIC Network Interface Card:
i.e. the Ethernet card of the IED
NPS Negative phase sequence.
NVD Neutral voltage displacement:
Equivalent to residual overvoltage protection.
NXT Abbreviation of “Next”:
In connection with hotkey menu navigation.
o
A small circle on the input or output of a logic gate:
Indicates a NOT (invert) function.
O/P Abbreviation of “output”.
Opto An optocoupled logic input:
Alternative terminology: binary input.
P1 Used in IEC terminology to identify the primary CT terminal polarity:
Replace by a dot when using ANSI standards.
P2 Used in IEC terminology to identify the primary CT terminal polarity:
The non-dot terminal.
PCB Printed circuit board.
Ph Abbreviation of “Phase”:
Used in distance settings to identify settings that relate to phase-phase faults.
PICS Protocol Implementation Conformance Specification:
Defines the IEC 61850 services implemented in an IED, with reference to the ACSI.
PN> Wattmetric earth fault protection:
Calculated using residual voltage and current quantities.
Pol Abbreviation of “Polarizing”:
Typically the polarizing voltage used in making directional decisions.
PSL Programmable scheme logic:
The part of the relay’s logic configuration that can be modified by the user, using the
graphical editor within MiCOM S1 Studio software.
Qx Isolator number x (from 1 to 6).
R A resistance.