GE 845 Instruction Manual page 335

CHAPTER 4: SETPOINTS
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
Path:
Setpoints > Protection > Group 1(6) > Power > Directional Power 1(2)
FUNCTION
Range: Disabled, Trip, Alarm, Latched Alarm, Configurable
Default: Disabled
RCA
Range: 0 to 359° in steps of 1°
Default: 0°
This setting specifies the Relay Characteristic Angle (RCA) for the Directional Power
function. Application of this setting is threefold:
1. It allows the element to respond to active or reactive power in any direction (active
overpower/underpower, etc.).
2. Together with a precise calibration angle, it allows compensation for any CT and VT
angular errors to permit more sensitive settings.
3. It allows for required direction in situations when the voltage signal is taken from
behind a delta-wye connected power transformer and phase angle compensation is
required.
For example, the active overpower characteristic is achieved by setting DIR POWER 1
RCA to "0°," reactive overpower by setting DIR POWER 1 RCA to "90°," active underpower
by setting DIR POWER 1 RCA to "180°," and reactive underpower by setting DIR POWER 1
RCA to "270°".
PROTECTION
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