ABB SACE Emax 2 Series - Protection ROCOF

ABB | SACE Emax 2
118 | © 2013 ABB | 1SDH001000R0002 - L7804
Ekip Touch protection release | 13 - G Hi-Touch protections
Protection ROCOF
f28
t
t28
F
ROCOF
Path
Main page - Menu - Advanced protections
Function
The protection ROCOF protects against rapid frequency variations.
When the frequency variation exceeds the control threshold f28, the protection trips within a
fixed time t28.
It is also possible to characterize the protection according to the way in which frequency varies
(increase or decrease), or to consider both conditions.
f(Hz)
Time
failure
50/60 Hz
frequency
after failure
frequency
after failure
Figure 83
Parameters
It is possible to modify various parameters:
Parameter Description
Enabling Activates/deactivates the protection.
Threshold (f28)
It defines the maximum frequency variation allowed, which if
exceeded activates the protection.
It is represented as an absolute value (Hertz).
Trip Direction
It defines whether the protection monitors increases, decreases, or
both variations.
Time (t28)
This is the delay time between the exceeding of the f28 threshold
and the sending of the opening command
Protection ROCOF has Trip Enable, see page 93.