SACE Emax 2 UL [EL]

SACE EMAX 2 NEW LOW VOLTAGE POWER C I RCUI T BRE AKERS TO ANS I C37 / UL 1066 / CSA STANDARDS

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— Description of protection functions

Dual setting of protections : Ekip Hi-Touch can store a set of alternative parameters for all protections. This second series (set B) can replace, if necessary, the default series (set A) by an external command. The command can be given when the network configuration is edited, for example when an emergency source is activated in the system, changing the load capacity and the short-circuit levels. Another typical applica- tion is helping protect the operator opposite the switchgear against the electric arc. In this case, protec- tion delays are minimized to safeguard the operator (Set A), whereas in the absence of an operator the pro- tections are set to help ensure selectivity with the circuit breakers downstream (Set B). It is possible to activate series B by: • Digital input available with an Ekip Signalling module; • Communication network, by means of one of the Ekip Com communication modules; • Directly from the Ekip Hi-Touch display; • By a settable internal time, after the circuit-breaker has closed. Differential ground fault (Rc - ANSI 87N) : helps protect against internal ground fault on generator wind- ing. The toroid is required to hug the active conductors and the ground conductor. Rc protection is inte- grated by a dedicated residual current rating plug and the external toroid.

L1 L2 L3

The specific functions for generator protections are described below. For each it is possible to choose the operating mode: active, only alarm or deactivated. All the voltage and frequency protections also operate when the circuit- breaker is open, enabling the fault to be identified before the closing of the circuit breaker. Voltage controlled overcurrent protection (S(V) - ANSI 51V) : protection frommaximum current with a con- stant trip time (t = k) that is sensitive to the voltage value. The set current threshold, following a voltage drop, decreases by steps or linearly.

t20

KsxI20

I20

In stepmode (controlledmode) the protection is tripped at the set threshold (I20) if the voltage is above U, whereas it is tripped at the lower threshold of the factor Ks (I20 * Ks) if the voltage is belowU.