GE 845 Instruction Manual page 403

CHAPTER 4: SETPOINTS
Real Power Demand
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
The Real Power Demand is monitored by comparing it to a Pickup value. If the Real 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 > Real Power Demand 1(X)
FUNCTION
Range: Disabled, Alarm, Latched Alarm, Configurable
Default: Disabled
MEASUREMENT TYPE
Range: Blk Interval, Exponential, Rolling Dmd
Default: Blk Interval
This 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
This setpoint sets the time required for steady-state Real 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
This setpoint sets the time period over which the Real 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 kW in steps of 0.1 kW
Default: 1000.0 kW
This setting sets the Real Power Demand Pickup level. The absolute value of real power
demand is used for the Pickup comparison.
BLOCK
Range: Off, Any FlexLogic operand
Default: Off
OUTPUT RELAYS 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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