2 Engineering2.1 Selection of devicesDS7 Soft starter 09/16 MN03901001Z-EN www.eaton.com 332 Engineering2.1 Selection of devicesThe DS7 soft starters can be designed for standard motors in standardapplications (such as pumps, fans, conveyor belts etc.) according to thetechnical data provided in the Appendix.A more specific design is required for drives with a high starting torque orhigh inertia. The following information must be known for correct deviceselection:• the overload cycle of the machine,• The start-up time for DOL starting or for star/delta starting,• the maximum starting current,• the load cycle,• the load that the motor is required to drive.The values of the moments of inertia must also be known for a more precisedesign. These values enable you to select the most suitable soft starter.The relevant procedure is described in the manual MN03902001Z-EN(“Design of soft soft starters”) and applies generally to all Eaton soft starters.The necessary key data of the DS7 soft starter series that is also required forthis design (rated operational current, overload capacity, root mean squarecurrent at nominal switching frequency) is provided in the Appendix in thetechnical data.Connecting to a higher-level PLC through SmartWire-DT requires softstarters with part no. DS7-34D…-D… (hereafter referred to as “DS7-SWD”).These soft starters can be controlled and monitored via SmartWire-DT, andtheir parameters can be configured via SmartWire-DT as well.￫ In connection with a motor-protective circuit-breaker (PKE),current can be monitored and additional protective functions canbe activated via SmartWire-DT(￫ chapter 8, “SmartWire-DT”).￫ The devices in the DS7-34D…-D series can only be used inconjunction with the SmartWire-DT connection. They cannot berun via control signal terminals.By setting the 1-0-A switch to position 1, the correspondingmotor can be started directly in manual mode (￫ chapter 8,“SmartWire-DT”).
