2. Metering management system
Modbus
A serial communication protocol developed by the Modicon company in
1979. Originally used for communication in PLCs and RTU devices.
MV
Medium voltage
NC
Normally closed
P2P
peer-to-peer
PC
1. Personal computer
2. Polycarbonate
PCM600
Protection and Control IED Manager
Peak-to-peak
1. The amplitude of a waveform between its maximum positive value and
its maximum negative value
2. A measurement principle where the measurement quantity is made by
calculating the average from the positive and negative peak values with-
out including the DC component. The peak-to-peak mode allows consid-
erable CT saturation without impairing the performance of the operation.
Peak-to-peak
with peak back-
up
A measurement principle similar to the peak-to-peak mode but with the
function starting on two conditions: the peak-to-peak value is above the
set start current or the peak value is above two times the set start value
PLC
Programmable logic controller
PPS
Pulse per second
PRP
Parallel redundancy protocol
PTP
Precision Time Protocol
RAM
Random access memory
RCA
Also known as MTA or base angle. Characteristic angle.
RJ-45
Galvanic connector type
RMS
Root-mean-square (value)
RoHS
Restriction of hazardous substances
ROM
Read-only memory
RSTP
Rapid spanning tree protocol
RTC
Real-time clock
RTD
Resistance temperature detector
RTS
Ready to send
SAN
Single attached node
SBO
Select-before-operate
SCADA
Supervision, control and data acquisition
SCL
XML-based substation description configuration language defined by IEC
61850
Single-line dia-
gram
Simplified notation for representing a three-phase power system. Instead
of representing each of three phases with a separate line or terminal, only
one conductor is represented.
SMT
Signal Matrix tool in PCM600
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1MRS758755 C
Glossary
REC615 & RER615
Technical Manual
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