LIB 520 High-voltage software module
LCD Liquid crystal display
LDCM Line data communication module
LDD Local detection device
LED Light-emitting diode
LNT LON network tool
LON Local operating network
MCB Miniature circuit breaker
MCM Mezzanine carrier module
MIM Milli-ampere module
MPM Main processing module
MVAL Value of measurement
MVB Multifunction vehicle bus. Standardized serial bus originally
developed for use in trains.
NCC National Control Centre
NOF Number of grid faults
NUM Numerical module
OCO cycle Open-close-open cycle
OCP Overcurrent protection
OEM Optical Ethernet module
OLTC On-load tap changer
OTEV Disturbance data recording initiated by other event than start/
pick-up
OV Overvoltage
Overreach A term used to describe how the relay behaves during a fault
condition. For example, a distance relay is overreaching when
the impedance presented to it is smaller than the apparent
impedance to the fault applied to the balance point, that is, the
set reach. The relay “sees” the fault but perhaps it should not
have seen it.
PCI Peripheral component interconnect, a local data bus
PCM Pulse code modulation
PCM600 Protection and control IED manager
PC-MIP Mezzanine card standard
Section 25 1MRK 511 401-UUS A
Glossary
646 Bay control REC670 2.2 ANSI
Application manual