SEL 279

[lsuengineer]

I am in the process of setting an SEL 279 relay. Does anyone know any good rules of thumb for the 25D setting? I have seen ranges from 17 cycles to 120 cycles. The setting is developed from a formula in the SEL manual that depends on "slip frequency" and "closing angle". Please help.

 

[Milko]

The adjust of 25D is very easy. Here you have a example;
25DV =21 V
25DT =50 Cycles
system 50 Hz, 400 kV.





Melquiades
Protective Relay
Testing and Commissioning