![background image](http://html.mh-extra.com/html/abb/sace-tmax-xt5/sace-tmax-xt5_operation-and-maintenance-manual_2240068.webp)
ABB | SACE Tmax XT
66 | © 2019 ABB | 1SDH002039A1002 - ECN000093027 - Rev. A
Protections | 6 - ROCOF protections
6 - ROCOF protections
The ROCOF Protection package is available by default for Ekip G Hi-Touch and configurable in the remaining
models as additional SW package
The protection is described below:
ROCOF Protection
f28
t
t28
Hz/s
ROCOF
Function
ROCOF protection protects against rapid frequency variations: the protection sends a TRIP command if the
frequency changes faster than control variation f28 set in the unit for longer than t28.
f(Hz)
Time
failure
50/60 Hz
frequency
after failure
frequency
after failure
Figure 31
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 95)
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 f28
establishes the maximum admissible frequency variation rate over time; the
protection trips if this rate is exceeded.
The value is given as absolute value (Hz/s) Fn) and can be set within the
range: 0.4 Hz/s to 10 Hz/s in 0.2 Hz/s steps
0,6 Hz/s
Trip Direction
Establishes whether the protection monitors an increase (
Up
), a decrease
(
Down
) or both variations (
Up
and
Down
)
Up or Down
Time f28
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
0,5 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).
Содержание SACE Tmax XT5
Страница 2: ...ABB SACE Tmax XT 2 2019 ABB 1SDH002039A1002 ECN000093027 Rev A ...
Страница 4: ...II 2019 ABB SACE Tmax XT 1SDH002039A1002 ECN000093027 Rev A ...
Страница 204: ...ABB SACE Tmax XT 202 2019 ABB 1SDH002039A1002 ECN000093027 Rev A Other accessories 5 Testing and Programming ...
Страница 205: ...1SDH002039A1002 ECN000093027 Rev A ...