Multifunction Protection
The SIPROTEC 4 7SJ63 can be used as a protective control and monitoring relay for distribution feeders and transmission lines of any voltage in networks that are earthed, low-resistance earthed, unearthed, or of a compensated neutral point structure. The relay is suited for networks that are radial or looped, and for lines with single or multi-terminal feeds. Regarding the time-overcurrent/ directional time-overcurrent protection the characteristics can be either definite time, inverse time or user-defined.

The SIPROTEC 4 7SJ63 is equipped with motor protection applicable for asynchronous machines of all sizes. Motor protection comprises undercurrent monitoring, starting time supervision, restart inhibit, locked rotor.

The relay provides easy-to-use local control and automation functions. The number of controllable switchgear depends only on the number of available inputs and outputs. The integrated programmable logic ( CFC) allows the user to implement their own functions, e.g. for the automation of switchgear ( interlocking) . The user is able to generate userdefined messages as well.

The flexible communication interfaces are open for modern communication architectures with control systems.
Extensive communication options:
• Integration into substation control system
• Service interface via modem for protection engineer