ABB SACE Tmax XT2, Руководство пользователя

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1SDH002031A1002 ECN000092998 Rev. B SACE Tmax XT2
– XT4 | 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.
NOTE: the S2 protection, differently from S protection, only has one trip curve with fixed
time and does not have thermal memory
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:

Protection summary table with the formulas for calculations (page 78)

Chart with tripping curve (page 85)
Parameters
Parameter Description Default
Enable
Enables/disables protection and availability on menu of the
parameters
OFF
Trip Enable
Activates/deactivates the open command: if disabled, the alarm
and the lapsing of the protection time are managed only as
information
ON
Threshold I5
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
2 In
Time t5
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
0.05 s
Zone
Selectivity
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
OFF
Selectivity
time
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
0.04 s
StartUp
enable Activates/deactivates the function and display availability of the
combined parameters, see page 73 for details
OFF
StartUp
threshold
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 .
2 In
StartUp time
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.
0.1 s
Constraints, limitations, and additional functions

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.