GE 845 Instruction Manual page 405

CHAPTER 4: SETPOINTS
Reactive Power
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
The Reactive Power Demand is monitored by comparing to a Pickup value. If the Reactive
Power Demand Pickup is ever equalled or exceeded, the relay can be configured to cause
an alarm or signal an output relay.
Path: Setpoints > Monitoring > Functions > Demand > Reactive Power Demand 1(X)
FUNCTION
Range: Disabled, Alarm, Latched Alarm, Configurable
Default: Disabled
MEASUREMENT TYPE
Range: Blk Interval, Exponential, Rolling Dmd
Default: Blk Interval
The setting sets the measurement method. Three methods can be applied.
THERMAL 90% RESPONSE TIME
Range: 5 min, 10 min, 15 min, 20 min, 30 min
Default: 15 min
The setpoint sets the time required for a steady state Reactive Power to indicate 90% of
the actual value and allows the user to approximately match the response of the relay
to analog instruments. The setpoint is visible only if MEASUREMENT TYPE is "Thermal
Exponential".
TIME INTERVAL
Range: 5 min, 10 min, 15 min, 20 min, 30 min
Default: 20 min
The setpoint sets the time period over which the Reactive Power Demand calculation is
to be performed. The setpoint is visible only if MEASUREMENT TYPE is "Block Interval" or
"Rolling Demand".
PICKUP
Range: 0.1 to 300000.0 kvar in steps of 0.1 kvar.
Default: 1000.0 kvar
The setting sets the Reactive Power Demand Pickup level. The absolute value of reactive
power demand is used for the Pickup comparison.
BLOCK
Range: Off, Any FlexLogic operand
Default: Off
OUTPUT RELAY X
For details see Common
EVENTS
Range: Enabled, Disabled
Default: Enabled
TARGETS
Range: Disabled, Self-reset, Latched
Default: Self-reset
Setpoints.
MONITORING
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