ABB | SACE Tmax XT
42 | © 2019 ABB | 1SDH002039A1002 - ECN000093027 - Rev. A
Protections | 1 - Standard Protections
S2 Protection
I5
t
t5
I
S2
Function
S2 protection functions in the same way as S protection: if the current of one or more phases exceeds
threshold I5 for longer than time t5, the protection activates and sends a TRIP command.
NOTE:
unlike S protection, S2 protection only has one fixed time trip curve and has no thermal
memory
It is independent of S protection, thus thresholds and functions of the two protections can be programmed
so as to take advantage of different plant solutions (example: signaling with S and open command with S2 or
vice versa, or both S and S2 for signaling or tripping).
To check and simulate the trip times in relation to all the parameters, please consult:
• the summary table of the protections with the calculation formulas (page 79)
• the graph with trip curve (page 86)
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.
ON
Threshold I5
Establishes the value that activates the protection and contributes
towards calculating the trip time.
The value is given as both absolute value (A) and relative value (In) and
can be set within the range: 0.6 In to 10 In, in 0.1 In steps
4 In
Time t5
This is the trip time of the protection.
The value is given in seconds and can be set within the range: 0.05 s
to 0.8 s, in 0.01 s steps
0,05 s
ZoneSelectivity
Activates/deactivates the function and selectivity time availability on
the display (page 72)
NOTE
: if both S and S2 selectivities are activated, the input and
output are shared with the OR function; to stimulate inputs and
outputs, it is sufficient for even only one of the two to be
activated
OFF
Selectivity time
This is the trip time of the protection with the zone selectivity function
activated and selectivity input not present (page 72)
The value is given in seconds and can be set within the range: 0.04 s
to 0.2 s, in 0.01 s steps
0,04 s
StartUp enable
Activates/deactivates the function and availability of the associated
parameters on the display (page 75)
OFF
StartUp
Threshold
Protection threshold valid during Startup time, in the conditions in
which the function is activated (page 75)
The value is given as both absolute value (A) and relative value (In) and
can be set within the range: 0.6 In to 10 In, in 0.1 In steps
4 In
StartUp Time
This is the time for which the StartUp threshold remains activated and
is calculated from the moment the activation Threshold is exceeded
(page 75)
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
• threshold I5 must be higher than threshold I1 (if S2 protection is activated)
• the block functions and type of selectivity can also be accessed by means of the service connector (via
Ekip Connect) or communication via system bus (page 74)
