ABB MPS-C 2000 Quick Start Manual - Page 5

Browse online or download pdf Quick Start Manual for Protection Device ABB MPS-C 2000. ABB MPS-C 2000 8 pages. Microprocessor-based protection and metering devices for low voltage power circuit breakers
Also for ABB MPS-C 2000: Instructions Manual (18 pages)

Print Page

System Overview

Major components of the system include current sensors, the MPSC-2000, and a magnetic latch trip device, all of which are

mounted integral to the circuit breaker to provide complete protection for overcurrent, short circuit and ground faults. A current

sensor is integrally mounted on each phase of the breaker to supply a value of current flowing in the MPSC-2000 which is directly

proportional to the current passing through the primary circuit. When the value of current in the primaries exceeds the trip unit

setting thresholds for a given time in Long Time, Short Time and/or Ground functions, the MPSC-2000 sends a signal to actuate

the magnetic latch, which trips the circuit breaker. Instantaneous function tripping occurs in the same manner without an

intentional time delay. On three phase, four wire, wye systems provisions are made for input from a separately mounted sensor

to obtain a residual connection of all four sensors for sensitivity to ground currents. Refer to IB 6.1.2.8-1A for available phase and

ground current sensor ratings.

The MPSC-2000 Long Time trip element algorithm samples the current, calculates the root mean square (RMS) value of system

current, and trips when the RMS current is above the trip threshold. Short time and instantaneous tripping remain based on peak

sensing methods to avoid an unnecessary delay caused by an RMS calculation.