ABB RELION REX640 - 4.6 Frequency protection; 4.6.1 Frequency protection FRPFRQ (ANSI 81); 4.6.1.1 Identification; 4.6.1.2 Function block

4.5.10.10 Technical data
Table 878: PHVPTOV Technical data
Characteristic Value
Operation accuracy Depending on the frequency of the measured
voltage: f
n
±1.5 % of the set value or ±0.002 × U
n
Reset ratio Depends on the set Relative hysteresis
Operate time accuracy in definite time mode ±1.0 % of the set value or ±20 ms
4.6 Frequency protection
4.6.1 Frequency protection FRPFRQ (ANSI 81)
4.6.1.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Frequency protection FRPFRQ f>/f<,df/dt 81
4.6.1.2 Function block
Figure 513: Function block
4.6.1.3 Functionality
The frequency protection function FRPFRQ is used to protect network components
against abnormal frequency conditions.
The function provides basic overfrequency, underfrequency and frequency rate-of-
change protection. Additionally, it is possible to use combined criteria to achieve
even more sophisticated protection schemes for the system.
The function contains a blocking functionality. It is possible to block function
outputs, timer or the function itself.
Protection functions
1MRS759142 F
920 REX640
Technical Manual