18 S611 Soft Starter MN03902011E—May 2012 www.eaton.comStarting/Stopping OptionsThe following starting options are available in the S611 soft starter:Voltage Ramp StartThis is the most commonly used mode of soft starting. Starting at an initial value set by theInitial Torque parameter, the voltage applied to the motor is gradually increased at a rate thatwill reach rated voltage at the end of the ramp time, set by the Soft Start Time parameter. Asthe voltage increases the motor develops torque that accelerates the load toward full speed.When the S611 senses that the motor has achieved synchronous speed, it quickly completesthe voltage ramp and closes the bypass contactor. (See figure below.)It should be noted that a lightly loaded motor takes less torque, and thus lower voltage andtime to accelerate to full speed. For this case the S611 will go into bypass before the rampreaches full voltage. In other words, the S611 will go into bypass before the Soft Start Timehas elapsed.Ramp StartKick Start—The Kick Start feature works in both the Voltage Ramp Start and Current LimitStart modes. By momentarily applying up to a two (2) second pulse of current to the motor, itprovides an initial boost in torque to overcome the static friction common in some applications.The level of torque boost is set by the Kick Start Torq parameter and the duration of the “kick”is set by the Kick Start Time. Setting the Kick Start Time to 0 disables this feature.InitialTorqueKickStartTorqKick Start Time100%Bypass BypassVoltageRamp RatedVoltageSoft Start TimetrStart RunTorqueTime (Seconds)100%Start RunSpeedTime (Seconds)www.comoso.com
