Category: ABB

Protection Function

Three Phase Current Protection

Functionality

The three-phase overcurrent protections is used as single-phase, two-phase

or three phase non-directional overcurrent and short-circuit protection for feeders.

The function starts when the current exceeds the set limit. 

The operate time characteristics for low stage is both DMT and IDMT and high stage is definite time (DT) definite minimum. 

The instantaneous stage always operates with the DT characteristic.

In the DT mode, the function operates after a predefined operate time and resets when the fault current disappears. 

The IDMT mode provides current-dependent timer characteristics.

Earth Fault Protection

Functionality

The earth-fault function is used as non-directional earth-fault protection for feeders.

The function starts and operates when the set current exceeds the set limit.

The relay can measure earth current by internal calculation (IEC variant only) and

also by external core balance current transformer input.

Separate earth fault input is available in relay which can be connected to corebalance current transformer of 1A secondary.

The operate time characteristic for low stage has both DT and IDMT and high stage has only

definite time (DT) .. In the DT mode, the function operates after a predefined

operate time and resets when the fault current disappears.

Principle of Operation

The three-phase overcurrent unit continuously measures the phase currents of the protected object. 

On detection of a fault the relay starts, trips the circuit breaker, records fault data etc. in accordance with the application.

REF601 has overcurrent protection with low set, high set and very high set module.

The product support both DMT and IDMT times in low set (I>) while high set (I>>) and Very high set (I>>>) supports to DMT timings. 

As the fault current exceeds the set value, trip time counting is started and start LED on front panel of relay glows ON. 

If fault current falls down below the drop off value of set current for 40 ms before trip time gets complete, start LED

will be turned off and trip count will become zero. 

Trip time will start from zero for next time when the fault current exceeds the set value again.

After a healthy trip, Start LED will be turned off and again if fault current exceeds threshold, start LED will be turned ON again.

In case of healthy trip, after trip time get elapsed relay generates the trip command which operates the Trip relay contacts as per user selected

configuration. Two LED indications on front plate of relay i.e. Trip (common trip indication) and Trip Ip and one signaling contact (XK2.3 –

XK2.4) will also be activated for user as Trip indication.

Optional function

Communication on MODBUS RTU Protocol

Other Functions

Self Supervision

The IED is provided with an extensive self-supervision system which

continuously supervises the software and the electronics.

It handles runtime fault situations and informs the user about an existing fault via the LHMI.

When in an IED internal fault is detected, the green Ready LED ceases to

glow and the self-supervision output contact is activated. Internal fault

indications have the highest priority on the LHMI. None of the other

LHMI indications can override the internal fault indication. An indication

about the fault is also shown as a message on the LHMI. The text IRF with

an additional text message, a code is shown to indicate the fault type.

The user can try to eliminate the fault by restarting the IED. If the fault is

still found, the IED stays in internal fault mode. All other output contacts

are released and locked for the internal fault.

The self-supervision signal output operates on the closed circuit principle.

Under normal conditions the relay is energized and the contact gap 5-6 in

connector XK2 is closed. If the auxiliary power supply fail or an internal

fault is detected, the contact gap 5-6 is opened.

Overview

REF601 is a dedicated feeder protection relay, intended for the protection

and control of utility substations and industrial power systems. 

The relay is compatible with the Rogowski coil sensor for current measurement. 

The feeder protection relay REF601 is designed to unleash the advantages of

current sensors for protection and control in medium voltage applications.

The REF601 features compact size and ease of use. 

The features include:

Sensor input for phase current measurement

Earth current measurement internally or externally through CBCT

Three-stage overcurrent protection

Two-stage earth-fault protection

Inrush detection for stability during transformer charging

Local and remote control of circuit breaker

Trip Circuit Supervision

Lockout function

100 event logs

Two analogue fault records

Non-resettable trip counter

On-line current measurements in primary value

Comprehensive local HMI

Universal auxiliary supply

Compact design suitable for circuit breaker or panel mounting

Optional MODBUS RTU communication

Non-volatile memory for setting and fault records

Self-supervision

User selectable rated frequency 50 / 60 Hz

Operation Functionality

Relay functions

REF601 offers pre-configured functionality which facilitates easy and fast

commissioning of switchgear. To emphasize the relay’s simplicity of usage,

only application specific parameters needs to set within the relay’s intended area of application.

The settings can be changed by LHMI (local human-machin interface) or

through optional communication interface MODBUS master with setting capability.

The relay offers protection, control, measurement and condition monitoring functionality.

Intended audience

This manual addresses system engineers, installation and commissioning

personnel, who use technical data during engineering, installation and

commissioning, and in normal service. system engineer must have a

thorough knowledge of protection systems, protection equipment,

protection functions and the configured functional logics in the IEDs.

The installation and commissioning personnel must have a basic

knowledge in handling electronic equipment.

This manual addresses Protection and control engineer responsible for

planning, pre-engineering and engineering. The protection and control

engineer must be experienced in electrical power engineering and have

knowledge of related technology, such as communication and protocols.

The manual also addresses the operator, who operates the IED on a daily

basis. The operator must be trained in and have a basic knowledge of

how to operate protection equipment. The manual contains terms and

expressions commonly used to describe this kind of equipment.

General

This manual

This manual contains application and functionality descriptions and

connection diagrams, input and output signals, setting parameters and

technical data. The manual can be used as a technical reference during

the engineering phase, installation and commissioning phase, and during

normal service. The manual can also be used when calculating settings.

Instructions on how to operate the IED during normal service once it has

been commissioned and it can be used to find out how to handle

disturbances or how to view calculated and measured network data in

order to determine the cause of a fault.

communication module (SLM)

The optical serial channel and LON channel module is used to connect an IED to the communication that use SPA,

 LON, or IEC60870–5–103. 

The module has two optical ports for plastic/plastic, plastic/glass, or glass/glass.

Line data communication module (LDCM)

The line data communication module is used for binary signal transfer. 

Each module has one optical port, one for each remote end to which the IED communicates.

Alternative cards for Long range (1550 nm single mode), Medium range (1310 nm single mode) and

Short range (900 nm multi mode) are available.

GPS time synchronization module (GSM)

This module includes the GPS receiver used for time synchronization. 

The GPS has one SMA contact for connection to an antenna.

Transformer input module (TRM)

The transformer input module is used to galvanically separate and transform the secondary currents and voltages generated by the measuring transformers. 

The module has twelve inputs in different combinations.

High impedance resistor unit

The high impedance resistor unit, with resistors for pick-up value setting and a voltage dependent

resistor, is available in a single phase unit and a three phase unit. 

Both are mounted on a 1/1 19 inch apparatus plate with compression type termnals.

Binary input/output module (IOM)

The binary input/output module is used when only a few input and output channels are needed. 

The ten standard output channels are used for trip output or any signalling purpose. 

The two high speed signal output channels are used for applications where short operating time is essential. 

Eight optically isolated binary inputs cater for required binary input information.

mA input module (MIM)

The milli-ampere input module is used to interface transducer signals in the –20 to +20 mA range

from for example OLTC position, temperature or pressure transducers.

The module has six independent, galvanically separated channels.

Optical ethernet module (OEM)

The optical fast-ethernet module is used to connectan IED to the communication buses 

(like the station bus) that use the IEC 61850-8-1 protocol. 

The module has one or two optical ports with ST connectors.

Serial SPA/IEC 60870-5-103 and LON

Hardware modules

Power supply module (PSM)

The power supply module is used to provide the correct internal voltages and full isolation between the terminal and the battery system. 

An internal fail alarm output is available.

Binary input module (BIM)

The binary input module has 16 optically isolated inputs and is available in two versions, 

one standard and one with enhanced pulse counting capabilities on the inputs to be used with the pulse counter function. 

The binary inputs are freely programmable and can be used for the input of logical signals to any of the functions.

They can also be included in the disturbance recording and event-recording functions. 

This enables extensive monitoring and evaluation of operation of the IED and for all associated electrical circuits.

Binary output modules (BOM)

The binary output module has 24 independent output relays and is used for trip output or any signal ling purpose.

The auto-reclose for single-, two- and/or three phase reclosing includes priority circuits for multi-breaker arrangements. 

It co-operates with the synchrocheck function with high-speed or delayed reclosing.

High set instantaneous phase and earth overcurrent, four step directional or un-directional delayed phase and earth overcurrent,

thermal overload and two step under and overvoltage functions are examples of the available functions allowing the

user to fulfill any application requirement.

The IED can also be provided with a full control and interlocking functionality including co-operation 

with the synchrocheck function to allow integration of the main or back-up control.

The advanced logic capability, where the user logic is prepared with a graphical tool, 

allows special applications such as automatic opening of disconnectors in multi-breaker arrangements, closingof breaker rings, load transfer logics etc. 

The graphical configuration tool ensures simple and fast testing and commissioning.

Serial data communication is via optical connections to ensure immunity against disturbances.

The wide application flexibility makes this product an excellent choice for both new installations and the refurbishment of existing installations.