ABB Relion REX640
Freely configurable all-in-one protection and control relay, modular and scalable hardware and software
ABB Relion REX640
ABB Relion REX640 is powerful, freely configurable all-in-one protection and control relay for primary distribution. Relion REX640 provides protection and control for a complete range of applications including feeder, line differential, transformer, voltage, busbar, capacitor bank, motor, generator and interconnection protection as well as automatic voltage regulation for on-load tap changers and Petersen coil protection and auto-synchronization. ABB Relion REX640 is designed fully compliant with the IEC/ ANSI and CN standards and offer optimal cyber security, promoting secure connectivity and safeguard our customers’ network.
ABB’s protection and control relays are available for original equipment manufacturers (OEM), panel builders and Engineering, Procurement and Construction (EPCs) partners to incorporate in their own installations or for use in repair, retrofit and upgrade projects.
ABB Relion REX640 leverages the same configuration software as all ABB Relion protection and control products. Relion REX640 offers a fully modular hardware and software allowing for high customization and easy adaptation to changing protection requirements throughout the relay life cycle. Relion REX640 protection relays are available in two different case widths: a narrow case offering five module slots and a standard case offering seven module slots. Software options are identical for both case sizes.
Product scope
REX640
- Feeder protection
- Bay control
- Transformer protection
- Line distance protection
- Line differential protection
- Motor protection
- Generator protection
- Busbar protection
REX615
- Feeder protection
- Bay control
- Transformer protection
- Line distance protection
- Line differential protection
- Motor protection
- Generator protection
- Busbar protection
Customer benefits
Compact Design & Installation
<ul> <li>Fully modular hardware and software for maximum flexibility and easy adaption to changing protection requirements throughout the entire relay life cycle </li> <li>Available in two hardware sizes, standard and narrow, to suit a variety of switchgear, applications and protection schemes </li> </ul>Configuration & Commissioning
<ul> <li>Complete application coverage with one freely configurable device for flexible and cost-effective tailoring to application-specific requirements </li> <li>User friendly PCM600 tool </li> </ul>Protection & Monitoring
<ul> <li>Ready-made application packages for convenient and smooth ordering </li> <li>Optimal situational awareness and usability with application-driven LHMI (local human-machine interface)/SHMI (switchgear human-machine interface) </li> </ul>Services for ABB Relion
- Trainings - remotely or at our facilities in Finland
- Support - by local "agency" or by our manufacture for level 3
- Select the right relay
- Technical documentation
Frequently Asked Questions
REX640 is designed to complement and extend the Relion portfolio, rather than simply replace earlier generations. It is particularly suited for applications that require higher performance, scalability, and advanced communication and cyber security capabilities, such as digital substations.
REX640 is intended for advanced primary protection, control, monitoring, and measurement in medium‑voltage and sub‑transmission networks. It is well suited for utilities and industries that require flexible application configurations and high availability.
The earlier Relion 615 series relays focused on defined, application‑specific protection, whereas REX640 is a modular and software‑configurable platform. It supports more complex protection schemes, higher processing capability, and greater flexibility to adapt over the relay’s lifecycle.
Yes. REX640 is highly configurable through application software and flexible hardware options. Users can tailor protection, control, communication, and monitoring functions to meet specific grid requirements without hardware redesign, enabling easier adaptation as networks evolve.
REX640 is designed to operate in both conventional and digital substation environments. It supports modern communication protocols and architectures, enabling seamless integration with digital substation solutions, including process and station bus concepts.
Cyber security is built into the design of the REX640. The relay supports secure communication, user access control, and compliance with recognized cyber security standards, helping utilities protect critical grid infrastructure against evolving cyber threats.
Yes. REX640 is designed for long lifecycle support, with software‑based updates that allow new functions and improvements to be introduced without replacing hardware. This reduces maintenance effort and helps future‑proof investments.
REX640 integrates with ABB’s established engineering, configuration, and asset management tools, enabling consistent workflows across the Relion product family and simplifying training and operations.
Yes. REX640 meets the needs of utilities modernizing their grids and is also suitable for industrial applications that require advanced protection reliability, flexibility, and secure communication.
Yes, ABB’s Relion protection and control relays feature a plug-in design that makes performing maintenance or replacement easy. It is also easy to change the relay as requirements change – just modifying it with a software application package.
It is easy to modify ABB Relion’s medium-voltage protection and control relays. It’s simply a question of installing a new software application package to meet the specific need(s).