Controller Connections - ABB RELION REX640 Technical Manual

Section 9
Control functions
9.11.5
1574

Controller connections

Voltages
PASANCR supports zero-sequence voltage measurement from busbar or from coil.
Busbar measurement is, for example, an open-delta connection of phase-to-earth
voltage transformers. Coil measurement uses the coil's own secondary measurement
winding. Voltage measurement setting is used to select the active measurement.
Available options are "Busbar" and "Coil".
Phase-to-phase voltage AB must be connected to the controller. If only the phase
voltages are measured, the voltage U_AB is calculated internally in the protection
relay.
Coil position
The controller supports two possibilities for the coil position measurement. Position
Meas mode setting is used to select the active coil position measurement. Available
options are:
• "Pos. indication": Using only the RTD input module to measure the resistance
value from the arc suppression coil potentiometer with COIL_POS input and to
convert it into corresponding coil position according to the linearization table.
• "Pos. ind. and meas.": Using both COIL_POS and IRES signals. IRES is arc
suppression coil current measurement using conventional CTs or sensors.
Special attention should be paid to the accuracy of the current signals at low
amplitudes. Additionally, high accuracy can be ensured by applying
measurement class CTs and sensors. Current measurement improves controller
speed and accuracy. The recommendation for the CT is a primary current
equivalent to the coil's maximum current and accuracy class 0.5S or better. The
IRES signal is not sufficient for the controller as it does not allow manual control
of the coil if it is disconnected from the network.
All voltage and current signals are measured using the value of the filtered
fundamental frequency component (DFT). Hence, the harmonics are always
suppressed.
Status information
The connection status (COIL_STS) information from the adjustable arc suppression
coil disconnector or circuit breaker should be wired to the controller. Also, fixed
parallel coil status (FIXCOIL_STS) and the parallel resistor status
(RESISTOR_STS) should be wired to the controller if they are present in the system.
Inactive status information signal means that the device is not connected and active
status information signal means that the device is connected.
Outputs
The following outputs should be considered in order to ensure correct operation of the
controller if a fixed parallel coil or parallel resistor is installed in the network:
1MRS759142 C
REX640
Technical Manual