User manual 09/2009 - Schneider Electric

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User manual 09/2009 - Schneider Electric

The Protection FunctionSteady StateThe Micrologic 6 E-M trip unit considers the application to be in steady state according to the followingcriteria:• Start: As soon as startup ends• End: As soon as the 10% of Ir pick-up is crossed in a negative direction by the motor currentOperating DiagramThe diagram below shows the 2 operating states for a motor application:1 Compact NSX circuit breaker status (green = ON position)2 Contactor status (green = ON position)3 Current in the motor application4 Operating states:A: Startup B: Steady state (the active states are shown in green)Protection FunctionsThe figure and table below define the protection functions for Micrologic 6 E-M trip units:No. Parameter Description Function0 In Trip unit setting range: Minimum setting/maximum setting = trip unit In rating1 Ir Long time protection pick-up L2 Cl Long time protection trip class3 Isd Short time protection pick-up S4 tsd Short time protection time delay5 Ii Instantaneous protection pick-up I6 Ig Ground fault protection pick-up G7 tg Ground fault protection time delayIunbal Phase unbalance protection pick-uptunbal Phase unbalance protection time delayFunction : Adjustable : Non-adjustableEach function is reviewed in detail on the following pages.56 LV434104 09/2009

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