GE 845 Instruction Manual page 252

INPUTS
4–124
TRIP DROPOUT DELAY
Range: 0 to 600 s in steps of 1 s
Default: 0
This setpoint selects a fixed time interval to delay dropping out the output signal after
being generated.
TRIP OUTPUT RELAY X
For details see Common
ALARM FUNCTION
Range: Disabled, Alarm, Latched Alarm
Default: Disabled
The selection of Alarm or Latched Alarm setting enables the alarm function.
ALARM TYPE
Range: Over, Under
Default: Over
This setting determines if alarm pickup will occur when the analog input is over or under
the programmed threshold.
ALARM PICKUP
Range: -500000 to 500000 units in steps of 1 unit
Default: 10
This setpoint provides the alarm pickup level in engineering units as defined in the
setting.
ALARM DROPOUT RATIO
Range: 2 to 20 in steps of 1%
Default: 5%
This setting represents the variation of pickup value, in percentage of pickup, at which
the alarm element will effectively drop out. The drop out ratio is defined as follows:
• Drop Out = pickup – pickup * dropout ratio /100, when ALARM TYPE is Over
• Drop Out = pickup + pickup * dropout ratio /100, when ALARM TYPE is Under
For example, if the pickup level is 5000 µA, ALARM TYPE is set to "Over" and DROPOUT
RATIO set to "10%", the actual dropout will be 4500 µA. Conversely, if the ALARM TYPE is
"Under" with the same dropout ratio, the actual dropout will be 5500 µA.
ALARM PICKUP DELAY
Range: 0 to 600 s in steps of 1 s
Default: 2
This setpoint will operate the element if the alarm pickup condition is maintained for a
longer time than the delay time set here.
ALARM DROPOUT DELAY
Range: 0 to 600 s in steps of 1 s
Default: 0
This setpoint selects a fixed time interval to delay dropping out the output signal after
being generated.
ALARM OUTPUT RELAY X
For details see Common
BLOCK
Range: Any FlexLogic operand
Default: Off
Setpoints.
Setpoints.
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 4: SETPOINTS