Page 68 - Sace Emax 2 Manual for design engineers
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Continued from the previous page                                   ABB | SACE Emax 2
                                     Parameter    Description                                         Default
                                                  This is the voltage that determines the change in trip threshold I20;
                                                  the behavior differs, depending on the mode selected  (1)
                                     Threshold Ul                                                     1 Un
                                                  The value is given as both absolute value (Volts) and relative value (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 I20
                                                  trip threshold calculation:
                                                   • with voltage reading < Uh (and ≥ Ul), the threshold changes
                                     Threshold Uh  gradually  (1)                                     1 Un
                                                   • with voltage reading ≥ Uh, the threshold is I20
                                                  The value is given as both absolute value (Volts) and relative value (Un)
                                                  and can be set within the range: 0.2 Un to 1 Un in 0.01 Un steps
                                                  I20 threshold calculation constant.
                                     Threshold Ks  The value is given as percentage of threshold I20 and can be set   0,6 I20
                                                  within the range: 0.1 I20 to 1 I20, in 0.01 steps
                                                  This is the trip time of the protection.
                                     Time t20     The value is given in seconds and can be set within the range: 0.05 s  0.1 s
                                                  to 30 s, in 0.01 s steps


                                    (1) Trip threshold (depending on the operating curve)
                                     Mode     Voltage reading     Trip threshold
                                              < UI                Ks x I20
                                     Scal
                                              ≥ UI                I20
                                              < UI                Ks x I20
                                     Lin
                                              ≥ Ul (e < Uh)       ((I20 x ( 1 - Ks ) x ( U  - Uh ) ) / (Uh - Ul) ) + I20
                                                                                  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 83).


                     S(V) Protection Function
                                    S2(V) protection functions in the same way as S(V) protection and protects against short-circuits, with
                  t                 threshold sensitive to the voltage value.
                       I21    S2(V)  It is independent of S(V) protection, thus thresholds and functions of the two protections can be programmed
                                    so as to take advantage of different plant solutions (example: signaling with S(V) and open command with
                                    S2(V) or vice versa, or both S(V) and S2(V) for signaling or tripping).
                            t21
                                    If the current of one or more phases exceeds threshold I21 for longer than time t21, the protection activates
                                    and sends a TRIP command.
                                  I
                                    Threshold I21, after a voltage drop, varies in two different modes:
                                     •  Step provides for a stepped variation, depending on parameters Ul2 and Ks2.
                                     •  Lin (linear) provides for a dynamic variation, depending on parameters Ul2, Uh2 and Ks2.
                                             I                                      I


                                            I21                                    I21



                                       Ks2 x I21                              Ks2 x I21




                                                               Ul2    V                     Ul2        Uh2    V

                                    Figure 23
                                    To check and simulate the trip times in relation to all the parameters, please consult:
                                     •  the summary table of the protections with the calculation formulas (page 93)
                                     •  the graph with trip curve (page 104)

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       66 | © 2020 ABB |  1SDH001330R1002 - ECN000134959 - Rev. A                Ekip Touch - Protections | 4 - Voltage Advanced protections
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