ABB | SACE Tmax XT
58 | © 2019 ABB | 1SDH002039A1002 - ECN000093027 - Rev. A
Protections | 4 - Frequency protections
OF Protection
f13
t
t13
f
OF
Function
The protection sends a TRIP command if the grid frequency read by the unit exceeds threshold f13 for longer
than t13.
The protection excludes itself if the maximum value of the line-to-line voltage is less than 30 V.
To check and simulate the trip times in relation to all the parameters, please consult:
• summary table of the protections with the operating characteristics (page 80)
• the graph with trip curve (page 91)
Parameters
Parameter
Description
Default
Enable
Activates/deactivates the protection and its availability in the
parameters menu
OFF
Trip Enable
Activates/deactivates transmission of the open command: if disabled,
the alarm and exceedance of protection time are only managed as
information
OFF
Threshold f13
Establishes the value that activates the protection.
The value is given as both absolute value (Hertz) and relative value (Fn)
and can be set within the range: 1 Fn to 1.1 Fn in 0.001 Fn steps
1,1 Fn
Time t13
This is the trip time of the protection; the value is given in seconds and
can be set within a range: 0.06 s to 300 s, in 0.01 s steps
3 s
Limitations and additional functions
The block functions can also be accessed by means of the service connector (via Ekip Connect) or by
connection to the system bus (page 75).
UF2 Protection
f17
t
t17
f
UF2
Function
UF2 protection functions in the same way as UF protection: the protection sends a TRIP command if the grid
frequency read by the unit drops below threshold f17 for longer than t17.
It is independent of UF protection, thus thresholds and functions of the two protections can be programmed
so as to take advantage of different plant solutions (example: signaling with UF and open command with UF2
or vice versa, or both for signaling or tripping).
The protection excludes itself if the maximum value of the line-to-line voltage is less than 30 V.
To check and simulate the trip times in relation to all the parameters, please consult:
• summary table of the protections with the operating characteristics (page 80)
• the graph with trip curve (page 91)
Parameters
Parameter
Description
Default
Enable
Activates/deactivates the protection and its availability in the
parameters menu
OFF
Trip Enable
Activates/deactivates transmission of the open command: if disabled,
the alarm and exceedance of protection time are only managed as
information
OFF
Threshold f17
Establishes the value that activates the protection.
The value is given as both absolute value (Hertz) and relative value (Fn)
and can be set within the range: 0.9 Fn to 1 Fn in 0.001 Fn steps
0,9 Fn
Time t17
This is the trip time of the protection; the value is given in seconds and
can be set within a range: 0.06 s to 300 s, in 0.01 s steps
3 s
Limitations and additional functions
The block functions can also be accessed by means of the service connector (via Ekip Connect) or by
connection to the system bus (page 75).
