RET650 - Transformer protection

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

RET650 offers an optimum ‘off-the-shelf’, ready-made solution for the protection of two- and three-winding transformers. The type-tested variant of RET650 IEDs (Intelligent Electronic Device) is delivered equipped and configured with complete functionality and with default parameters for easy handling of products – from ordering, engineering, and commissioning to reliable operation.

The 650 series IEDs (Intelligent Electronic Device) have a number of useful features, such as a significantly reduced number of parameter settings and extended IED HMI functionality, including 15 dynamic three-color indication LEDs per page, on up to three pages, and configurable push-button shortcuts for different actions. 

In the 650 series IEDs, the most basic parameters are set before delivery from the factory. You only need to set the parameters specific to your application. This allows you to quickly take your IEDs into operation. The application manual includes setting examples to support your protection engineers.

Relion – Complete confidence

Transformer protection RET650 IEDs belong to the Relion protection and control product family. The Relion product family offers a wide range of products for the protection, control, measurement, and supervision of power systems. To ensure interoperable and future-proof solutions, Relion products have been designed to implement the core values of the IEC 61850 standard. With Hitachi Energy's leading-edge technology, global application knowledge, and experienced support network, you can be completely confident that your system performs reliably – in any situation.

Unrivaled sensitivity and speed

RET650 offers the best possible coverage for power transformer winding turn-to-turn faults and the unique negative sequence internal/external fault discriminator is faster than a conventional stabilized transformer differential protection function. It also enables extremely sensitive protection to detect evolving internal faults so that the system can be tripped before a more severe fault with serious damages occurs. RET650 places low requirements on the primary CTs and no interposing CTs are needed.

The low impedance restricted earth-fault function for all directly or low impedance earthed windings provide excellent stability for external faults. Having individual protection for each winding without the need for harmonics stabilization ensures high sensitivity and fast tripping. The additional directional zero-sequence current criterion of this function increases security.

Overcurrent functions provide the necessary back-up protection. The thermal overload function prevents transformer damage caused by overload. Breaker failure protection allows high-speed back-up tripping of surrounding breakers and re-tripping of the own breaker.

RET650 provides you with a future-proof concept based on application flexibility, which makes it an excellent choice for both new and retrofit installations. The integration of the main protection and a range of back-up protection functions within the IED improve your power system performance. It also reduces hardware engineering and installation time as well as space and spare parts requirements.