ABB Relion 650 series RET650 Product Manual page 10

Transformer protection RET650
Product version: 1.1
IEC 61850/ ANSI
Function
block
name
SAPTUF 81
SAPTOF 81
SAPFRC 81
10
Function description
Underfrequency function
Overfrequency function
Rate-of-change frequency protection
1MRK 504 127-BEN -
Issued: February 2011
Transformer
4 4 4
4 4 4
2 2 4
ABB