Cooper Low Impedance Bus Differential Relay M-LIB3, Operation Manual

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S150-34-1
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GENERAL CHARACTERISTICS AND OPERATION
1.12 Modular Low Impedance Bus Bar Protection M-LIB3
The M-LIB system is constituted of a number of modular units, which can be combined to suit to any
busbar configuration and allow for easy extension.
1.13 Main features
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Low impedance and low burden on main CTS.
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High stability with zone biased differential elements and CT saturation detectors.
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High speed of operation.
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High reliability: duplicated measuring circuits, CTs’ secondary circuits supervision, wide and
consistent setting ranges
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Self-contained input CTs for main zone and for check zone feature without duplication of main CTs.
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Self-contained isolator repeat relays switching at secondary of the zone input CTs.
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Self-contained discrepancy alarm relays
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Multivoltage power supply.
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Comprehensive self-diagnostic.
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User friendly MMI.
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Real time and recorded measurements.
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Event records and oscillography
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RS 485 serial port with ModBus protocol.
1.14 Component Modules
The system includes three basic modules:
1.14.1 M-BF3 = Income/Feeder Breaker input module (SCE1577)
Including :
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sets of three CTs. 1 set for the Main Zone and 1 for the Check Zone.
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CT saturation detectors.
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bistable isolator repeat relays for switching the secondary circuits of the input CTs and the zone
trip input signal.
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Time delayed isolator discrepancy alarm feature
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Power supply unit