Term Description
POST Power On Self Test
POTT Permissive Over Reach Transfer Tripping
PRP Parallel Redundancy Protocol
PSB Power Swing Blocking, to detect power swing/out of step functions (ANSI 78).
PSL
Programmable Scheme Logic: The part of the relay’s logic configuration that can be modified by
the user, using the graphical editor within S1 Studio software.
PT Power Transformer
PTP Precision Time Protocol
PUR A Permissive UnderReaching transfer trip scheme (alternative terminology: PUTT).
Q Quantity defined as per unit value
R Resistance
RBAC Role Based Access Control
RCA Relay Characteristic Angle - The center of the directional characteristic.
REB Redundant Ethernet Board
REF Restricted Earth Fault
Rev. Indicates an element responding to a flow in the "reverse" direction
RMS / rms
Root mean square. The equivalent a.c. current: Taking into account the fundamental, plus the
equivalent heating effect of any harmonics.
RP Rear Port: The communication ports on the rear of the IED
RS232 A common serial communications standard defined by the EIA
RS485 A common serial communications standard defined by the EIA (multi-drop)
RST or Rst Reset generally used in the context of reset functions in circuit breaker control.
RSTP Rapid Spanning Tree Protocol
RTD Resistive Temperature Device
RTU Remote Terminal Unit
Rx Receive: Typically used to indicate a communication transmit line/pin.
SBS Straight Binary Second
SC Synch-Check or system Synchronism Check.
SCADA Supervisory Control and Data Acquisition
SCL Substation Configuration Language
SCU Substation Control Unit
SEF Sensitive Earth Fault
SHP Self Healing Protocol
SIR Source Impedance Ratio
SMV Sampled Measured Values
SNTP Simple Network Time Protocol
SOA Service Oriented Architecture
SOAP Simple Object Access Protocol
SOC Second of Century
SOTF Switch on to Fault protection. Modified protection on manual closure of the circuit breaker.
SP Single pole.
SPAR Single pole auto-reclose.
SPC Single Point Controllable
SPDT Single Pole Dead Time. The dead time used in single pole auto-reclose cycles.
Appendix A - Symbols and Glossary MiCOM P747
412 P747-TM-EN-1
To Next Page
Loading...
