My friend I think you have a temporal solution for the problem.
Change the conection in the relay- the wiring from 1250/1 to the analog input for CT 1 A secondary. the same for the CT 1250/5 to input for CT 5 A secondary. Then check the differential current with secondary inyection.
Please...
The most important test before a relocation that must be done is the FRA Test (Frecuency Response Analizer). This test checks the mechanical integrity of the transformer and is performed before and after the relocation.
The FRA and Excitation test, together, will give you the change of health...
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
