ABB RET670 Transformer Protection User Guide

RET670 - Transmission transformer protection

For reliable protection and control of all types of power transformers and reactors

RET670 – optimized for transmission applications

RET670 IEDs provide customized or pre-configured protection solutions for any type of transformer and shunt reactor application. 

The customized RET670 gives you the freedom to select functionality entirely according to your needs. 

The pre-configured RET670 variants simplify handling since the basic functionality is included and pre-configured. 

If needed, you can add optional functions to increase the functionality of the pre-configured RET670 

IEDs to meet the specific requirements of your transformer or shunt reactor.

The extremely fast differential protection function with automatic CT ratio matching and vector group compensation, 

makes RET670 the ideal solution for the most demanding applications. 

Furthermore, one RET670 IED can be extended to contain two differential protection functions to protect the most advanced system configurations. 

This transformer protection IED is designed to operate correctly over a wide frequency range in order to accommodate

power system frequency variations during disturbances and generator start-up and shut-down. 

It has very low requirements on the main CTs, and no interposing CTs are required.

RET670 features also several functions for local and remote apparatus control on all sides of the transformer. 

Secure bay and station wide interlocking allows you to avoid dangerous or damaging switchgear operations and to ensure personnel safety.

Protection functions

The IED offers directional and non-directional overcurrent and thermal overload protection as

well as directional and non-directional earth-fault protection. 

Some standard configurations allow as an option admittance-based, harmonics-based or wattmetric-based earth-fault protection to be

used in addition to directional earth-fault protection. 

Further, the IED features sensitive earth-fault protection, phase discontinuity protection, transient/intermittent earth-fault protection, 

overvoltage and undervoltage protection, residual overvoltage protection, positive-sequence undervoltage 

and negativesequence overvoltage protection. 

The outstanding I/O capability in REC670 enables control of several bays with complete measurement with only one IED. 

For instance, one REC670 IED is capable of handling control of all apparatuses 

in one entire diameter in 1 ½ breaker arrangement including breaker failure protection for all breakers.

The REF 543 feeder terminal is designed for protection, control, 

measurement and supervision in medium voltage networks.

The REF 543 feeder terminal can be used with different kinds of switchgear, 

including single busbar, double busbar and duplex systems.

The protection functions also support different types of networks, such as, isolated neutral networks, 

resonant-earthed networks and partially earthed networks. 

REC670 IEDs (Intelligent Electronic Device) provide control solutions for any type of switchgear and different switchgear configurations. 

The customized REC670 gives you the freedom to select the functionality entirely according to your needs. 

The pre-configured REC670 variants simplify handling since the basic functionality is included and pre-configured. 

If needed, you can add optional functions to easily increase the functionality of 

the REC670 IEDs to meet the specific requirements of your switchyard.

REC670 integrates advanced voltage control for transformers in a substation in a single IED. 

The IEDs feature a large HMI for local control and instant access to important data, 

such as settings, events and disturbance information.

REF611 is a dedicated feeder protection relay designed for the protection, control, measurement

and supervision of utility substations and industrial power systems.

The feeder protection relay REF611 can be supplied either with directional or non-directional 

overcurrent and earth-fault protection. 

Directional earth-fault protection is mainly used in isolated neutral or compensated networks, 

whereas the non-directional earth fault protection is intended for directly or low-impedance earthed neutral networks.

REF611 is a member of ABB’s Relion® product family and part of its 611 protection and control series of relays.

For optimized control and reliable operation of your switchyard, the REC670 is your best choice for transmission applications.