The new, digital protection TSL-9r type may operate as a bus bar protection or/and as a breaker failure protection. It can be adjusted to any arrangement of the switchyard. It consists of one central unit and appropriate number of bay units (depending on number of bays of the switchyard) communicating with the central unit via optical fibre cable.


Its modular construction enables easy adaptation to changing arrangement of a substation when it is expanded. Changing the primary nominal current of the current transformers, and programming the working algorithm accordingly to arrangement of the switchyard, and change of setup – are programmable and easy to implement with a notebook.

The protections locates and correctly reacts to faults between the breaker and the current transformer, has an internal event and fault recorders. Communication with the control system can be performed via IEC 61850 and 870-5-103 protocols, using optical fibre cable or other accordingly to Purchasers demands.