GE Multilin G650, Manual

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GEK-113285A G650 Generator Protection & Control System 2-7
2 PRODUCT DESCRIPTION 2.4 TECHNICAL SPECIFICATIONS
2
2.4 TECHNICAL SPECIFICATIONS
NOTE: TECHNICAL SPECIFICATIONS ARE SUBJECT TO CHANGE WITHOUT NOTICE
2.4.1 PROTECTION ELEMENTS
Phase and ground units use as operation magnitude the current value received by the unit in current inputs, while the
neutral unit uses the calculated current value from the three phase currents.
The isolated ground unit will be used only for those applications where the neutral is completely isolated, and it uses the
fifth CT of the unit. This CT has a sensitivity that is 10 times higher than the universal model (connected to 1A or 5A
transformers). Therefore, it does not admit such a high permanent overload.
2.4.1.1 PHASE TIME OVERCURRENT (51PH/51PL)
Current Input Phasor (without harmonics) or RMS
Rated current For connection to 1 or 5 A CTs.
Pickup level 0.05 to 160.00 A in steps of 0.01 A
Dropout level 97% to 98% of the pickup level
Level Accuracy
Values at nominal frequency:
±
0.5% of the reading
±
10 mA from 0.05 to 10 A
±
1.5% of the reading for higher values.
Curve Shapes IEEE extremely / very / moderately inverse
IEC A/B/C/long-time inverse/short time inverse curve
IAC extremely / very / moderately inverse
ANSI extremely / very / normally / moderately inverse
I
2
t
Definite time
Rectifier curve
FlexCurve
™
A/B/C/D user curve
Curve Multiplier (Time Dial) 0.00 to 900.00 s in steps of 0.01 s
Reset type Instantaneous or time delayed according to IEEE
Timing accuracy Operate at > 1.03 times the pickup ±3% of operate time or
50 ms. (whichever is greater)
Voltage restraint Selectable by setting
Saturation Level 48 times the pickup level
Snapshot Events Selectable by setting