Page 58 - MCCB-XT5

Continued from the previous page ABB | SACE Tmax XT
Parameters
Parameter Description Default
Activates/deactivates the protection and its availability in the
Enable OFF
parameters menu
Activates/deactivates transmission of the open command: if
Trip Enable disabled, the alarm and exceedance of protection time are only OFF
managed as information
Curve Allows the operating mode, Step or Lin, to be selected Scal
Establishes the value that activates the protection and
contributes towards calculating the trip time.
Threshold I21 The value is given as both absolute value (amperes) and relative 1 In
value (In) and can be set within the range: 0.6 In to 10 In, in 0.1 In
steps
It is the voltage that determines the change in trip threshold I21;
the behavior differs, depending on the mode selected (1)
Threshold Ul2 The value is given as both absolute value (V) and relative value 1 Un
(Un) and can be set within the range: 0.2 Un to 1 Un in 0.01 Un
steps
The parameter is shown by the Lin curve and contributes towards
I21 trip threshold calculation:
• with voltage reading < Uh2 (and ≥ Ul2), the threshold changes
gradually (1)
Threshold Uh2 1 Un
• with voltage reading ≥ Uh2, the threshold is I21
The value is given as both absolute value (V) and relative value
(Un) and can be set within the range: 0.2 Un to 1 Un in 0.01 Un
steps
I21 threshold calculation constant.
Threshold Ks2 The value is given as percentage of threshold I21 and can be set 0,6 I21
within the range: 0.1 I21 to 1 I21, in 0.01 steps
This is the trip time of the protection.
Time t21 The value is given in seconds and can be set within the range: 0.1 s
0.05 s to 30 s, in 0.01 s steps

(1) Trip threshold (depending on the operating curve)
Mode Voltage reading Trip threshold
< UI2 Ks2 x I21
Scal
≥ UI2 I21
< UIs Ks2 x I21
Lin
≥ Ul2 (e < Uh2) ((I21 x ( 1 - Ks2 ) x ( U - Uh2 ) ) / (Uh2 - Ul2) ) + I21
mis
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 76).

56 | © 2022 ABB | 1SDH002039A1002 - ECN000212994 Protections | 4 - Voltage Advanced protections