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Contactor utilisation categories
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Current-limiting circuit breaker
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Disconnector
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Switch-disconnector
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function breaks the circuit under load conditions and the disconnection function
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Locked-rotor protection (Ijam)
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Long-start protection (Ilong)
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Phase-unbalance or phase-
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Starting current
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Starting time
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Time after which the motor ceases to draw the starting current and falls back to the
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Thermal image of the rotor
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Thermal protection
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Trip class
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Under-load protection (Iund)
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