Phase Current - GE G60 Instruction Manual

CHAPTER 5: SETTINGS

5.7.6 Phase current

5.7.6.1 Menu
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  PHASE CURRENT
 PHASE CURRENT

5.7.6.2 Inverse TOC curve characteristics
The inverse time overcurrent curves used by the time overcurrent elements are the IEEE, IEC, GE Type IAC, and I
curve shapes. This allows for simplified coordination with downstream devices.
If none of these curve shapes is adequate, FlexCurves can be used to customize the inverse time curve characteristics. The
definite time curve is also an option that can be appropriate if only simple protection is required.
Table 5-28: Overcurrent curve types
IEEE
IEEE Extremely Inverse
IEEE Very Inverse
IEEE Moderately Inverse
A time dial multiplier setting allows selection of a multiple of the base curve shape (where the time dial multiplier = 1) with
the curve shape ( ) setting. Unlike the electromechanical time dial equivalent, operate times are directly proportional
CURVE
to the time multiplier (
TD MULTIPLIER
or base curve values. Setting the multiplier to zero results in an instantaneous response to all current levels above pickup.
G60 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 5-116: Stator differential final output logic
 PHASE TOC 1


 PHASE TOC 2


 PHASE IOC 1



 PHASE IOC 4


 PHASE

 DIRECTIONAL 1
IEC
IEC Curve A (BS142)
IEC Curve B (BS142)
IEC Curve C (BS142)
IEC Short Inverse
) setting value. For example, all times for a multiplier of 10 are 10 times the multiplier 1
See page 5-221
See page 5-223
See page 5-224
GE type IAC
IAC Extremely Inverse
IAC Very Inverse
IAC Inverse
IAC Short Inverse
GROUPED ELEMENTS
2
t standard
Other
2
I t
FlexCurves A, B, C, and D
Recloser Curves
Definite Time
5-215
5