ABB RELION REX640 Technical Manual page 1433

1MRS759142 F
8 Measurement functions
8.1 Basic measurements
8.1.1 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 available in VPHMMXU.
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 the 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.
REX640
Technical Manual
If the measured data in LHMI or WHMI is within parentheses, there are
some problems to express the data.
Measurement functions
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