ABB RELION REL650 Operation Manual page 61

1MRK 500 125-UEN A
OLTC
OTEV
OV
Overreach
PCI
PCM
PCM600
PC-MIP
PMC
POR
POTT
Process bus
PSM
PST
PT ratio
PUTT
RASC
RCA
RISC
RMS value
RS422
RS485
RTC
RTU
SA
SBO
SC
SCL
SCS
SCADA
SCT
SDU
SLM
SMA connector
SMT
SMS
Operation manual
On-load tap changer
Disturbance data recording initiated by other event than start/pick-up
Overvoltage
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.
Peripheral component interconnect, a local data bus
Pulse code modulation
Protection and control IED manager
Mezzanine card standard
PCI Mezzanine card
Permissive overreach
Permissive overreach transfer trip
Bus or LAN used at the process level, that is, in near proximity to the
measured and/or controlled components
Power supply module
Parameter setting tool within PCM600
Potential transformer or voltage transformer ratio
Permissive underreach transfer trip
Synchrocheck relay, COMBIFLEX
Relay characteristic angle
Reduced instruction set computer
Root mean square value
A balanced serial interface for the transmission of digital data in point-
to-point connections
Serial link according to EIA standard RS485
Real-time clock
Remote terminal unit
Substation Automation
Select-before-operate
Switch or push button to close
Short circuit location
Station control system
Supervision, control and data acquisition
System configuration tool according to standard IEC 61850
Service data unit
Serial communication module.
Subminiature version A, A threaded connector with constant
impedance.
Signal matrix tool within PCM600
Station monitoring system
Section 8
Glossary
55