ABBDistributed busbar protection REB500 including line and transformer protection Product Guide

next disturbance (FIFO = First In, First Out).

This function is performed in a stand-alone 

mode in the bay unit (see page 7).

Note:

Stored disturbance data can be transferred via 

the central unit to other computer systems for 

evaluation by programs such as PSM505 [3]. 

Files are transferred in the COMTRADE format.

After retrieving the disturbance recorder data, 

it is possible to display them graphically with 

PSM505 directly.

Communication interface

Where the busbar protection has to communicate with a station automation system (SAS), 

a communication module is added to the central unit. The module supports the interbay 

bus protocols IEC 61850-8-1, IEC 60870-5-

103 and LON.

The IEC 61850-8-1 interbay bus transfers via 

either optical or electrical connection:

• differential current of each protection zone

• monitoring information from REB500 central unit and bay units

• binary events (signals, trips and diagnostic)

• trip reset command

Distributed busbar protection REB500

including line and transformer protection

• disturbance recording data (via MMS file 

transfer protocol)

• time synchronization with Simple Network 

Time Protocol (SNTP) 

• two independent time servers are supported. Server 2 as backup time

The LON interbay bus transfers via optical 

connection:

• differential currents of each protection zone

• binary events (signals, trips and diagnostic)

• trip reset command

• disturbance recording data (via HMI500)

• time synchronization

The IEC 60870-5-103 interbay bus transfers 

via either optical or electrical connection:

• time synchronization

• selected events listed in the public part

• all binary events assigned to a private part

• all binary events in the generic part

• trip reset command

Test generator

The HMI program (HMI500) which runs on a 

PC connected to either a bay unit or the central processing unit includes a test generator.

During commissioning and system maintenance, the test generator function enables the 

user to:

• activate binary input and output signals

• monitor system response.

• test the trip circuit up to and including the 

circuit-breaker 

• test the reclosure cycles

• establish and perform test sequences with 

virtual currents and voltages for the bay 

protection of the REB500sys

The test sequencer enables easy testing of 

the bay protection without the need to decommission the busbar protection. Up to seven 

se-quences per test stage can be started. The 

sequences can be saved and reactivated for 

future tests.

Isolator supervision

The isolator replica is a software feature without any mechanical switching elements. The 

software replica logic determines dynamically 

the boundaries of the protected busbar zones 

(protection zones). The system monitors any 

inconsistencies of the binary input circuits 

connected to the isolator auxiliary contacts 

and generates an alarm after a set time delay.

In the event of an isolator alarm, it is possible 

to select the behavior of the busbar protection:

• blocked

• zone-selective blocked

• remain in operation

Differential current supervision

The differential current is permanently supervised. Any differential current triggers a timedelayed alarm. In the event of a differential 

current alarm, it is possible to select the 

behavior of the busbar protection:

• blocked

• zone-selective blocked

• remain in operation

Trip redirection

A binary input channel can be provided to 

which the external signal monitoring the circuit-breaker air pressure is connected. Tripping is not possible without active signal. 

When it is inactive, a trip generated by the 

respective bay unit is automatically redirected 

to the station at the opposite end of the line 

and also to the intertripping logic to trip all the 

circuit-breakers connected to the same section of busbar.

The trip redirection can also be configured 

with a current criterion (current release criteria).

Distributed busbar protection REB500

including line and transformer protection

Page 13 

Human machine interface (HMI)

The busbar protection is configured and maintained with the aid of human machine interfaces at three levels.

Local HMI

The local display interface installed in the central unit and in the bay units comprises:

• a four-line LCD with 16 characters each for 

displaying system data and error messages

• keys for entering and display as well as 3 

LEDs for the display of trips, alarms and 

normal operation.

• in addition 20 freely programmable LEDs 

for user-specific displays on the bay unit 

500BU03 and central unit 500CU03.

The following information can be displayed:

• measured input currents and voltages 

• measured differential currents (for the busbar protection)

• system status, alarms

• switchgear and isolator positions (within 

the busbar protection function)

• starting and tripping signals of protection 

functions

External HMI (HMI500)

More comprehensive and convenient control 

is provided by the external HMI software running on a PC connected to an optical interface