Group: SIEMENS Infrastructure & Cities
Differential protection relay
SIEMENS Smart Grid
The SIPROTEC 7UT612 differential protection relay is used for fast and selective fault clearing of short-circuits in two winding transformers of all voltage levels and also in rotating electric machines like motors and generators, for short two terminal lines and busbars up to 7 feeders.
The specific application can be chosen by parameterization. In this way an optimal adaption of the relay to the protected object can be achieved.
In addition to the differential function a backup overcurrent protection for 1 winding / star point is integrated in the relay. Optionally, a low or high-impedance restricted earth-fault protection, a negative sequence protection and a breaker failure protection can be used. With external temperature monitoring boxes (RTD-boxes) a maximum of 12 temperatures can be measured and supervised in the relay. Therefore, complete thermal supervision of a transformer is possible.
The protection relay can be parameterized for use with three-phase and single-phase transformers. In addition to this, a thermal replica is integrated for the supervision of the ohmic losses in the plant.