ABB | SACE Tmax XT
64 | © 2019 ABB | 1SDH002039A1002 - ECN000093027 - Rev. A
Protections | 5 - Power protections
UP Protection
P23
t
t23
P
UP
Function
The protection sends a TRIP command if one or more of the active power values detected by the unit drop
below threshold P23 for longer than t23.
The protection is active also for negative (reverse) active power, but is independent from the RP protection
(protection against reverse active power).
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 94)
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 P23
Establishes the value that activates the protection.
The value is given as both absolute value (kW) and relative value (Sn)
and can be set within the range: 0.1 Sn to 1 Sn in 0.001 Sn steps
1 Sn
Time t23
This is the trip time of the protection; the value is given in seconds and
can be set within a range: 0.5 s to 100 s, in 0.5 s steps
1 s
StartUp enable
Activates/deactivates the function and availability of the StartUp Time
parameter in the menu
OFF
StartUp Time
This is the time for which the threshold remains disabled and is
calculated from the moment the activation Threshold is exceeded
The value is given in seconds and can be set within the range: 0.1 s to
30 s, in 0.01 s steps
0.1 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).
RQ Protection
Function
RQ protection protects against reactive power reversal; the threshold can be adjusted on the basis of the
active power.
The protection sends a TRIP command when inverse reactive power enters the TRIP area, determined by the
protection parameters and power value readings, for longer than t24.
Adjustment of constants Kq and Kq2 allows the trip threshold of the protection (determined by the intersection
of the two TRIP areas, whose limits depend on the parameters configured in the unit) to be changed.
Q
P
TRIP
Q24
kq
kq2
Q25
Figure 30
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 94)
Continued on the next page