ABB SACE Tmax XT2 User Manual page 38

S2 protection Function
S2 protection operates like S protection: if the current of one or more phases exceeds the I5
threshold for a time greater than t5, the protection is activated and sends the TRIP command.
It is independent of S protection and it is therefore possible to program thresholds and functions
of the two protections to take advantage of different system solutions (example: signaling with S
and opening command with S2 or vice versa, or S and S2 both for signaling or for tripping).
To verify and simulate the trip times based on all the parameters, see:


Parameters
Parameter
Enable
Trip Enable
Threshold I5
Time t5
Zone
Selectivity
Selectivity
time
StartUp
enable
StartUp
threshold
StartUp time
Constraints, limitations, and additional functions


1SDH002031A1002 ECN000092998
NOTE: the S2 protection, differently from S protection, only has one trip curve with fixed
time and does not have thermal memory
Protection summary table with the formulas for calculations (page 78)
Chart with tripping curve (page 85)
Description
Enables/disables protection and availability on menu of the
parameters
Activates/deactivates the open command: if disabled, the alarm
and the lapsing of the protection time are managed only as
information
Defines the value that activates protection and contributes to
calculating trip time.
The value is expressed both as an absolute value (Ampere) and as
a relative value (In), settable in a range: 0.6 In .. 10In with 0.1 In
step
This is the trip time of the protection.
The value is expressed in seconds, settable in a range:
0.05 s .. 0.4 s, with 0.01 s step
Activates/deactivates the function and the display availability of
selectivity time, see page 70 for details
in the presence of both S and S2 active selectivity, the
input and output are shared with an OR function: it is also
sufficient for just one of the two to be active to stimulate
inputs and outputs
This is the trip time of the protection with the zone selectivity
function active and the selectivity input not present see page 70for
details
The value is expressed in seconds, which are settable in a range:
0.04 s .. 0.2 s, with 0.01 s step
Activates/deactivates the function and display availability of the
combined parameters, see page 73 for details
Protection threshold valid during Startup time, in conditions in which
the function is active, see page 73 for details
The value is expressed both as an absolute value (Ampere) and as
a relative value (In), settable in a range:
0.6 In .. 10In with 0.1 In step .
This is the time for which the StartUp threshold is active, calculated
from tripping of activation threshold, see page 73 for details
The value is expressed in seconds, which are settable in a range:
0.1 s .. 30 s, with 0.01 s step.
The I5 threshold must be greater than the I1 threshold (if the S2 protection is active)
From the service connector (with Ekip Connect) or with system bus communication it is also
possible to access the block functions and the selectivity type, see page70.
Rev. B
Default
OFF
ON
2 In
0.05 s
OFF
0.04 s
OFF
2 In
0.1 s
SACE Tmax XT2 – XT4 | 38