Principle Of Operation; Measurement Supervision - ABB Relion 670 Series Technical Reference Manual

1MRK 505 208-UEN B
13.1.2
13.1.2.1
Technical reference manual
It is possible to calibrate the measuring function above to get better then class 0.5
presentation. This is accomplished by angle and amplitude compensation at 5, 30
and 100% of rated current and at 100% of rated voltage.
The power system quantities provided, depends on the actual
hardware, (TRM) and the logic configuration made in PCM600.
The measuring functions CMSQI and VMSQI provide sequential quantities:
• I: sequence currents (positive, zero, negative sequence, amplitude and angle)
• U: sequence voltages (positive, zero and negative sequence, amplitude and
angle).
The CVMMXN function calculates three-phase power quantities by using
fundamental frequency phasors (DFT values) of the measured current respectively
voltage signals. The measured power quantities are available either, as
instantaneously calculated quantities or, averaged values over a period of time (low
pass filtered) depending on the selected settings.

Principle of operation

Measurement supervision

The protection, control, and monitoring IEDs have functionality to measure and
further process information for currents and voltages obtained from the pre-
processing blocks. The number of processed alternate measuring quantities
depends on the type of IED and built-in options.
The information on measured quantities is available for the user at different locations:
• Locally by means of the local HMI
• Remotely using the monitoring tool within PCM600 or over the station bus
• Internally by connecting the analogue output signals to the Disturbance Report
function
Phase angle reference
All phase angles are presented in relation to a defined reference channel. The
General setting parameter PhaseAngleRef defines the reference.
Zero point clamping
Measured value below zero point clamping limit is forced to zero. This allows the
noise in the input signal to be ignored. The zero point clamping limit is a general
setting (XZeroDb where X equals S, P, Q, PF, U, I, F, IL1-3, UL1-3, UL12-31, I1,
I2, 3I0, U1, U2 or 3U0). Observe that this measurement supervision zero point
clamping might be overridden by the zero point clamping used for the
measurement values within CVMMXU.
Section 13
Monitoring
465