GE Multilin 850

CHAPTER 4: SETPOINTS PROTECTION
850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 4–191
FAST PATH:
Only Phase to Phase mode shall be selected when Delta is programmed for the Phase VT
Connection setting under System/Voltage Sensing.
PHASES FOR OPERATION
Range: Any One, Any Two, All Three
Default: Any One
This setting defines the number of voltages required for operation of the Timed UV
protection function.
PICKUP
Range: 0.00 to 1.50 x VT in steps of 0.01 x VT
Default: 0.90 x VT
This setting sets the phase Undervoltage pickup level specified as percent VT. For
example, a Pickup setting of 0.90xVT with 13800:115 VT translates into 12.42kV (or
103.5V secondary). If the Mode selection is Phase to Phase and Setpoints/ System Setup/
Voltage Sensing/ Phase VT Connection selection is Wye, the previous example will
translate to the Phase to Phase voltage value of 12.42kV x 1.732 = 21.51kV.
DROPOUT
Range: 102.00 to 150.00 %PKP in steps of 0.001 %PKP
Default: 102.00 %PKP
This setting sets the phase Undervoltage dropout level specified as a percentage of
Pickup. For example, a Dropout setting of 102 %PKP with 0.90 x VT as pickup and
13800:115 VT translates into 1.02 x 12.42kV = 12.67kV (or 105.57V secondary). If the
Mode selection is Phase to Phase and Setpoints/System Setup/Voltage Sensing/Phase
VT Connection selection is Wye, the previous example will translate to the Phase to
Phase voltage value of 12.67kV x 1.732 = 21.94kV.
DROPOUT DELAY
Range: 0.000 to 6000.000 s in steps of 0.001 s
Default: 0.000 s
This setting provides a definite time dropout delay. Instantaneous operation is selected
by a dropout time delay setting of 0.000 s.
MINIMUM VOLTAGE
Range: 0.00 to 1.50 x VT in steps of 0.01 x VT
Default: 0.20 x VT
This setting sets the minimum operating voltage for undervoltage pickup level specified
as percent of VT. For example, a minimum voltage setting of 0.20x VT with 13800:115 VT
translates into 2.76kV (or 23V secondary). If the Mode selection is Phase to Phase and
Setpoints/ System Setup/ Voltage Sensing/ Phase VT Connection selection is Wye, the
previous example will translate to a Phase to Phase voltage value of 2.76kV x 1.732 =
4.78kV.
COUNTER MODE
Range: Disabled, Enabled
Default: Disabled
This setpoint enables the counter based undervoltage protection. With this setting
enabled, the user can define the number of tolerated voltage drops and the total time
window for which these voltage drops are allowed.