GE G60 Instruction Manual page 460

GROUPED ELEMENTS
and the magnitude of the neutral and zero-sequence voltages |V
Therefore, for faults at a fraction k = 0.15 from the neutral grounding point, we set the operating quantities as follows:
The 100% stator ground settings are described as follows.
100% STATOR GND STG1 PICKUP
measure the operating quantity under various load conditions for a particular machine in order to optimize this setting.
This can be achieved using the actual values menu of the G60.
100% STATOR GND STG1 DELAY
established.
100% STATOR GND STG1 SUPV
the machine neutral and in the zero-sequence terminal voltage. The setting is entered as a per-unit value of the terminal
voltages. Different settings can be considered for stages 1 and 2 as one of them can be used for alarm and the other for
trip. The safe value of this setting can be established after putting a given machine into service and reading the quantity
from the relay under the
5
5.7.17.3 Third harmonic neutral undervoltage (ANSI 27TN)
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  STATOR GROUND  3RD HARM NTRL
UNDERVOLTAGE
 3RD HARM NTRL
 UNDERVOLTAGE
5-284
— This setting specifies a pickup level for the operating quantity. It can be beneficial to
— This setting specifies a time delay required to operate after the pickup condition is
— This setting specifies a signal level supervision for the vectorial sum of the third harmonic at
menu.
ACTUAL VALUES
Figure 5-163: Stator ground logic
3RD HARM NTRL UV

FUNCTION: Disabled
3RD HARM NTRL UV

PICKUP: 0.3000 pu
+ V | as:
N 0
Range: Disabled, Enabled
Range: 0.0010 to 3.0000 pu in steps of 0.0001
G60 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS
Eq. 5-43
Eq. 5-44