ABB Relion 670 Series Applications Manual page 501

1MRK 511 358-UUS A
Application manual
Preprocessing block shall only be used to feed functions within the same execution
cycles (e.g. use preprocessing block with cycle 1 to feed transformer differential
protection). The only exceptions are measurement functions (CVMMXN,
CMMXU,VMMXU, etc.) which shall be fed by preprocessing blocks with cycle 8.
When two or more preprocessing blocks are used to feed one protection function
(e.g. over-power function GOPPDOP), it is of outmost importance that parameter
setting DFTReference has the same set value for all of the preprocessing blocks
involved
Section 21
Basic IED functions
495