Basic Measurements - ABB RELION REX640 Technical Manual

1MRS759142 C
Section 8
8.1
8.1.1
REX640
Technical Manual
Measurement functions

Basic measurements

Functions
The three-phase current measurement function CMMXU is used for monitoring and
metering the phase currents of the power system.
The three-phase voltage measurement function VMMXU is used for monitoring and
metering the phase-to-phase voltages of the power system. The phase-to-earth
voltages are also available in VMMXU.
Single-phase voltage measurement function VAMMXU is used for monitoring and
metering the single-phase voltage of the power system.
The residual current measurement function RESCMMXU is used for monitoring and
metering the residual current of the power system.
The residual voltage measurement function RESVMMXU is used for monitoring and
metering the residual voltage of the power system.
The frequency measurement function FMMXU is used for monitoring and metering
the frequency of the power system.
The sequence current measurement CSMSQI is used for monitoring and metering the
phase sequence currents.
The sequence voltage measurement VSMSQI is used for monitoring and metering the
phase sequence voltages.
The frequency measurement FMMXU is used for monitoring and metering the power
system frequency.
The three-phase power and energy measurement PEMMXU is used for monitoring
and metering active power (P), reactive power (Q), apparent power (S) and power
factor (PF) and for calculating the accumulated energy separately as forward active,
reversed active, forward reactive and reversed reactive. PEMMXU calculates these
quantities using the fundamental frequency phasors, that is, the DFT values of the
measured phase current and phase voltage signals.
The information of the measured quantity is available for the operator both locally in
LHMI or WHMI and remotely to a network control center with communication.
Section 8
Measurement functions
1287