ABB 1MRK505352-BEN Distributed busbar protection

MOSFET technology and offer an improved trip-time performance.

A software logic enables the input and output channels to be assigned to the various functions.

A time stamp is attached to all the data such as currents, voltages, binary inputs, events and diagnostic information acquired by a bay unit.

Where more analog and binary inputs are needed, several bay units can be combined to form a feeder/bus coupler

bay (e.g. a bus coupler bay with CTs on both sides of the bus-tie breaker requires two bay units).

The bay unit is provided with local intelligence and performs local protection (e.g. breaker failure, end fault,

breaker pole discrepancy) as well as the event and disturbance recording.

In the event that the central unit is out of operation or the optical fiber communication is disrupted an alarm is generated. 

The bay unit will continue to operate and all local protection as well as the recorders (event and disturbance) will remain fully functional (stand-alone operation).

The hardware structure is based on a closed, monolithic casing and presented in two mounting solutions:

· Without LHMI: ideal solution if convenient access to all information via the central unit or by an existing

substation automation system is sufficient.

· With LHMI and 15 programmable LEDs (Figure 7): ideal solution for distributed and kiosk mounting (AIS), since

all information is available in the bay.

For this option it is possible to have the LHMI either built in or connected via a flexible cable to a fixed mounting position.

Additional plug-and-play functionality

Bay units can be added to an existing REB500 system in a simple way.

Due to the modular and flexible architecture of the software, integration of new units is easily achieved.

In the event of a failure, a bay unit can be easily replaced.

During system startup the new bay unit requests its address, this can be entered directly via its LHMI.

The necessary setting values and configuration data are then downloaded automatically Central unit (500CU04)

The hardware structure is based on a closed, monolithic casing.

The central unit is the system manager, i.e. it configures the system, contains the busbar replica, assigns bays

within the system, manages the sets of operating parameters, acts as REB500 process bus controller,

assures synchronization of the system and communicates with the station control and monitoring system.

The variables for the busbar protection function are derived dynamically from the process data provided by the bay units.

The process data is transferred to the central processor via the REB500 process bus interface.

The central unit is able to handle data from up to 60 bay units and evaluate up to 32 bus zones.

In addition to processing the protection zone data, the central unit provides a disturbance recorder for all 32 bus

zones, recording the main data of the busbar protection to facilitate quick fault analysis.

The central unit offers 9 binary inputs and 19 binary outputs for central commands and signals (e.g. external

bus zone trip, trip-reset etc.). Additional 9 binary inputs and 9 binary outputs are optional available.

The central unit comprises a local HMI with 15 programmable LEDs (Figure 8) including a front Ethernet

port for HMI connection within the local area network.