14
1MRS751802-MUM
Protection Relay
Technical Reference Manual, Standard Configurations
REX 521
1.4. Abbreviations
1.5. Related documents
Manuals for REX 521
ASCII American Standard Code for Information Interchange
CB Cicuit Breaker
CBFP Circuit-breaker Failure Protection function
CRC Cyclic Redundancy Check
CT Current transformer
DC Disconnector
DI Digital input
ES Earth switch
HMI Human-machine interface
HSPO High-speed power output
IDMT Inverse Definite Minimum Time
IRF Internal relay fault
LCD Liquid crystal display
LED Light-emitting Diode
MCB Miniature Circuit Breaker
MMI Man-machine interface
NC Normally closed
NO Normally open
NPS Negative Phase Sequence
PO Power output
RS Rogowski sensor
RTC Real-time clock
RTU Remote Terminal Unit
SA Substation automation
SO Signalling output
TCS Trip-circuit supervision
VD Voltage divider
VT Voltage transformer
• Technical Reference Manual, General 1MRS751108-MUM
• Operator’s Manual 1MRS751107-MUM
• Installation Manual 1MRS750526-MUM
• Technical Descriptions of Functions (CD-ROM) 1MRS750889-MCD
• Modbus Remote Communication Protocol for REX 521,
Technical Description
1MRS755017
• DNP 3.0 Remote Communication Protocol for REF 54_
and REX 521, Technical Description
1MRS755260