GE C70 Instruction Manual page 276

5.6 GROUPED ELEMENTS
a) MAIN MENU
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PATH: SETTINGS GROUPED ELEMENTS
 PHASE CURRENT
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5
b) INVERSE TOC CURVE CHARACTERISTICS
The inverse time overcurrent curves used by the time overcurrent elements are the IEEE, IEC, GE Type IAC, and I
dard curve shapes. This allows for simplified coordination with downstream devices.
If none of these curve shapes is adequate, FlexCurves may be used to customize the inverse time curve characteristics.
The definite time curve is also an option that may be appropriate if only simple protection is required.
Table 5–19: 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 (
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.
5-152
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SETTING GROUP 1(6)
 PHASE TOC1
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 PHASE TOC2
MESSAGE
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 PHASE TOC6
MESSAGE
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 PHASE IOC1
MESSAGE
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 PHASE IOC2
MESSAGE
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 PHASE IOC12
MESSAGE
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 PHASE
MESSAGE
 DIRECTIONAL 1
 PHASE
MESSAGE
 DIRECTIONAL 2
 PHASE CURRENT
MESSAGE
 UNBALANCE 1
 PHASE CURRENT
MESSAGE
 UNBALANCE 2
 PHASE CURRENT
MESSAGE
 UNBALANCE 3
IEC
IEC Curve A (BS142)
IEC Curve B (BS142)
IEC Curve C (BS142)
IEC Short Inverse
) setting. Unlike the electromechanical time dial equivalent, operate times are directly proportional
) setting value. For example, all times for a multiplier of 10 are 10 times the multiplier 1
C70 Capacitor Bank Protection and Control System

PHASE CURRENT
See page 5–157.
See page 5–157.
↓
See page 5–157.
See page 5–159.
See page 5–159.
↓
See page 5–159.
See page 5–160.
See page 5–160.
See page 5–163.
See page 5–163.
See page 5–163.
GE TYPE IAC
IAC Extremely Inverse
IAC Very Inverse
IAC Inverse
IAC Short Inverse
5 SETTINGS
5.6.4 PHASE CURRENT
2
t stan-
OTHER
2
I t
FlexCurves A, B, C, and D
Recloser Curves
Definite Time
GE Multilin