1SDH002031A1002 ECN000092998 Rev. B SACE Tmax XT2 – XT4 | 50
16 - Advanced Voltage Protections
The Advanced Voltage protections, configurable on all models as an additional software
package, are:
Short circuit with voltmeter control
Short circuit with voltmeter control
Function
The S(V) protection protects against short circuits, with a threshold sensitive to the voltage value.
If the current of one or more phases exceeds the I20 threshold for a time greater than t20, the
protection is activated and sends the TRIP command.
Following a voltage drop, the I20 threshold varies according to two different modes:
Scal (step) provides a step variation based on the parameters Ul and Ks.
Lin (linear) provides a dynamic variation based on the parameters Ul, Uh, and Ks.
To verify and simulate the trip times based on all the parameters, see:
Protection summary table with the formulas for calculations (page 79)
Chart with tripping curve (page 89)
Parameters
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
Enables the operating mode Scal or Lin to be selected:
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