GE 889 - Page 451

CHAPTER 4: SETPOINTS MONITORING
889 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL 4–321
PULSES PER REV
Range: 1 to 6 PPR in steps of 1 PPR
Default: 1 PPR
Number of pulses per revolution (PPR) is required to calculate the switching frequency of
the input pulses. Switching frequency can be calculated as follows.
Where:
PPR = pulses per revolution
RPM = rated speed
DIRECTION
Range: Underspeed, Overspeed
Default: Overspeed
This setting defines the mode for speed protection. When Direction is set to Underspeed,
the Trip and/or Alarm function picks up when the measured motor speed is below the
set pickup level. Likewise, when the Direction is set to Overspeed, the Trip and/or Alarm
function picks up when the measured motor speed is above the programmed pickup
level.
TRIP PICKUP
Range: 50 to 120% in steps of 1
Default: 110%
This setting specifies a pickup threshold for the trip function.
TRIP PICKUP DELAY
Range: 0.00 to 600.00 s in steps of 0.01 s
Default: 1.00 s
This setting specifies a pickup threshold for the trip function.
TRIP OUTPUT RELAY X
For details see Common Setpoints
.
ALARM FUNCTION
Range: Disabled, Alarm, Latched Alarm
Default: Disabled
This setting enables the speed protection Alarm functionality
ALARM PICKUP
Range: 50 to 120% in steps of 1
Default: 80%
This setting specifies a pickup threshold for the Alarm function.
ALARM PICKUP DELAY
Range: 0.00 to 600.00 s steps of 0.01 s
Default: 1.00 s
This setting specifies a time delay for the Alarm function.
ALARM OUTPUT RELAY X
For details see Common Setpoints
.
BLOCK
Range: Off, Any FlexLogic operand
Default: Off
The Speed protection can be blocked by any asserted FlexLogic operand.