Eaton S611 User Manual

Also see for S611: Installation leaflet Quick start installation guide Installation leaflet

Contents

64 S611 Soft Starter MN03902011E—May 2012 www.eaton.comAppendix E—Special Function OptionPump Control OptionThis option is intended to reduce the potential for waterhammer in a centrifugal pump system by using a starting andstopping algorithm developed for pump control. Upon a startcommand, the speed of the motor is increased, under thecontrol of the S611 soft starter microprocessor, to achieve agentle start. After the speed has reached its nominal value,the bypass contactors close and the pump operates as withany other starter. Upon a stop command, the bypasscontactors are opened and the motor speed is decreased in atapered manner, to gradually slow the flow until the motor isbrought to a stop. The start and stop ramp times are useradjustable and are to be set for the application requirements.The pump control option is a factory installed feature. Factoryinstalled options are designated by the eighth character inthe catalog number. Unmodified S611 soft starters have anN as their eighth character. S611 soft starters with the pumpcontrol option have a P as their eighth character, as inS611xxxP3S.InstallationInstall and wire your S611 soft starter per the instructionsfound in the beginning of this manual.SetupAll pump control parameters are set via the UI. Unitsconfigured with the pump control option can activate thisfeature by selecting the pump option under the UI “StartMethod” parameter.AdjustmentAll of the adjustments to the S611 soft starter are made asnoted in this user manual. The major difference between thestandard S611 soft starter and one with the pump startoption is the special algorithm for gentle start and stop withcentrifugal flow loads to minimize the potential for waterhammer.Using the UI, set the S611 soft start configurationparameters described below:The Start Ramp Time parameter adjusts the start ramp. It hasa standard range of 0.5–180.0 seconds. The factory default is20.0 seconds. The soft stop time is adjusted by Pump Stop,which has a range of 5.0–120.0 seconds with the factorydefault being 10.0 seconds. (Note: The Stop Ramp Timesetting used in non-pump S611s has no effect on units withthe Pump Control Option installed if start method is PumpStart.) These adjustments are application dependent, andshould be made to minimize any surge or water hammereffects. Typically Pump Stop would not be set short becausethe stop might not differ much from a coast-to-stop. The softstop time adjustment may often be in the range of 30–40seconds, but needs to be set appropriately for the systemrequirements. If reduction or elimination of water hammer isnot achieved, it may be necessary to lengthen Pump Stop toachieve the desired result. Note that long stop times willresult in greater motor heating than shorter stop times. Thiscan affect the number of start/stop cycles allowed per hourdue to the S611 soft starter or motor thermal limits.Pump Control Option100%trStart Soft Pump StopSpeedTime (Seconds)tsRunCoast to Stopwww.comoso.com