Page 137 - Sace Emax 2 Manual for design engineers

ABB | SACE Emax 2
Ekip Touch - Additional functions

1 - Zone Selectivity

Description Zone Selectivity is an evolution of time selectivity (see chapter "3 - Selectivity between ABB SACE circuit-
breakers"), in which a dialog is created between the trip units through input and output blocking signals: an
active input blocking signal means that the circuit-breaker must remain closed.
Specifically, if a trip unit with the function enabled detects a fault current higher than the threshold set for a
particular protection, it activates the output blocking signal for the protection and, before opening, checks
the corresponding input blocking signal:
• If the input is not active, the trip unit opens with a delay equal to the selectivity time set for the protection
(which must be lower than the protection tripping time).
• If the input is active, it opens only if the fault persists and with a delay equal to the tripping time of the
protection.

Zone Selectivity can be enabled via cabling (Hardware Selectivity) with ABB SACE circuit-breakers, not
Emax 2, where available.
Besides Hardware Selectivity, SACE Emax 2 circuit-breakers allow Logic Selectivity to be configured using
the communication via Link Bus between releases equipped with Ekip Link module. For further details,
consult paragraph “Zone Selectivity with SACE Emax 2 circuit-breakers".

Zone Selectivity with ABB SACE With electronic trip units not for ABB SACE Emax 2:
circuit-breakers • Zone selectivity can be implemented only for protections S I G and D (Directional).
• If the function is available, the circuit-breaker is equipped with two blocking outputs and two blocking
inputs that is, one output and one input for each S, I and G protection), or as an alternative two outputs
and two inputs for protection D (one output and one input per direction).
• Since only two blocking outputs and two blocking inputs are available, Zone Selectivity for protections S,
I and G and Directional Zone Selectivity are mutually excluding (to implement Directional Zone Selectivity,
the S, I and G protections must be disabled, and vice versa).
• To actuate Zone Selectivity, the releases must be equipped with auxiliary voltage to activate the outputs.
• Zone selectivity for S and I protection share the same restrain signal
• Each S G and D protection has two selectivity parameters: the function enabling parameter and selectivity
time, meaning the opening time of the circuit-breaker if the selectivity input is not active.
• For I protection the selectivity time is fixed (without possibilty to modify the value).
• The blocking outputs and inputs are considered active if the level is high (equal to the auxiliary voltage).
• For protection D, the selectivity time to be set is the same for both directions.

To obtain Zone Selectivity, the protections must be set, and the blocking outputs and must be wired, so that
only those circuit-breakers capable of isolating the overload or fault without the rest of the installation being
de-energized open. Regarding this:
• For each type of selectivity, definitions, operating principles, application fields, advantages and disadvantages,
requirements, indications for setting the protections and examples are provided in the Technical Application
Paper QT1 1SDC007100G0205 "Low voltage selectivity with ABB circuit-breakers".
• For Directional Selectivity, application examples are available in the White Paper 1SDC007401G0201
“Directional protection and directional zone selectivity”.

135 | © 2020 ABB | 1SDH001330R1002 - ECN000134959 - Rev. A Ekip Touch - Additional functions | 1 - Zone Selectivity