The REX 521 is primarily used in single-bus solutions for various protections using a single circuit breaker.

With pre-fabricated standard configurations, the unit can be used in different types of networks. Typical applications include input and output feeders in radially isolated neutral, resonant grounded, solid grounded and resistance grounded systems.

Scope

Protection, control, measurement and monitoring in medium voltage networks and for the protection of medium and large three-phase AC motors

Product advantages

Multifunctional protection

Product features

energized inputs for conventional current and voltage transformers

Versions with current and voltage sensor inputs also available

Prefabricated, standard configuration

REX 521 Relay Protection Unit

The REX 521 relay protection unit is designed for protection, control, measurement and monitoring of medium voltage networks.

Typical applications include incoming and outgoing feeders and substation protection.

The relay protection unit is equipped with energized inputs for conventional current and voltage transformers.

Hardware versions with current and voltage sensor inputs are also available.

The relay protection unit is based on a multiprocessor environment.

The human-machine interface includes an LCD display with different views for local use and informs the user with prompt messages.

Both hardware and software solutions utilize modern technology.

REX 521 is part of the Distribution Automation substation automation concept and further extends the functionality and flexibility of the concept.