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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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I3 — Description of protection functions 50% 150% 100% 200% L S I
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Overload (L - ANSI 49) : available with three different types of trip curve: 1. t = k/l 2 with inverse long time;
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Thresholds can be fine tuned (for example 1A for circuit-breaker E1.2 1000A) and timings can be set to the second directly from the display. The settable pre-alarm indicates the set threshold is reached before the protection is tripped.
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steady state
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start-up
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Time-delayed overcurrent (S - ANSI 51 & 50TD) : with constant tripping time (t = k), or with constant spe - cific let-through energy (t = k/l 2 ), this provides 15 current thresholds and 8 curves, for fine adjustment. The function can be excluded by setting the dip switch combination to “OFF”.
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Thermal memory : for L and S protection functions, this is used to protect components, such as transform- ers, from overheating following an overload. The function, which can be enabled by the Ekip Connect soft- ware, adjusts the protection tripping time according to the length of time that has elapsed since the first overload, taking into account the amount of heat generated.
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t1 L
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cold curve
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hot curve
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Instantaneous overcurrent (l - ANSI 50) : with tripping curve without intentional delay, it offers 15 tripping thresholds and can be excluded by setting the dip switch combination to “OFF”.
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steady state
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start-up
Closing on short-circuit (MCR): the protection uses the same algorithm of the protection l, limiting opera- tion to a settable time window from the closing of the circuit-breaker. The protection also can be disabled to protection l. The function is active with an auxiliary supply.
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Programmable instantaneous overcurrent (2I - ANSI 50): Second instantaneous tripping curve designed to mitigate against arc flashes (also referred to as RELT - Reduced Energy Let-Through). This protection can be adjusted from 1.5 to 15 x In, with a maximum setting of 18kA. The clearing time of the 2I protection is between 25 and 42ms at 60Hz (+5ms for 50Hz). Easy activation and I/O assignment, including positive feedback, can be implemented using the RELT Ekip Signalling 2K-3 module.
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Ground fault (G - ANSI 51N & 50NTD) : with tripping time independent of current (t = k) or constant specific let-through energy (t = k/l 2 ). The function can be excluded by setting the dip switch combination to “OFF”.
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t1
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