Scalability means machine OEMs can control costs and complexity by choosing exactly the intelligence level needed from a family of components to control all of their machines—from basic fixed-application machines to sophisticated, flexible-changeover models—with the same platform. Whether it's fieldbus compatibility or a full-blown motion controller, buying only the control power required saves money. That's a feature usually reserved for the most expensive control architectures.
At Pack Expo in Chicago this year, SEW-Eurodrive announces release of its new, scalable smart servo package, offering optimized, pre-defined combinations of motion controllers, servo drives, matching cables, synchronous servo motors and planetary gear units.
"All the components were designed to fit and work together as parts of the package," says Dave Ballard, SEW corporate engineering manager. "Sizing and selection are made easy using simple graphical tools and tables. Because everything is designed to work together smoothly, OEMs spend less time selecting, installing and starting the system."
The heart of the package is the new MoviTrac LTX servo drive. Available in single- and three-phase 230 Vac input with up to 16.5 A rated output current and up to 250% overload, this powerful, compact drive sets all relevant parameters automatically after reading the motor's electronic nameplate data in the Hiperface encoder, so startup should be quick and easy. The drive's simplicity allows setting the remaining parameters through an integrated keypad as an alternative to software. The LTX features onboard screw terminals for connection to preset and configurable I/O and built-in analog and step/direction input for the simplest applications.
For more advanced control, designers can couple the LTX with one of many varieties of SEW's communication gateways or motion controllers. "For speed control applications, communicate easily with fieldbus or Ethernet gateways," Ballard says. "You'll solve positioning applications with any of a number of scalable solutions from pre-defined application modules to freely programmable motion control of up to 16 axes."
For muscle, Ballard says the package relies on SEW's CMP synchronous motors and PSC planetary gear units. The CMP motor series provides standstill torque up to 7.1 Nm and up to 17.7 Nm of peak torque. "The low-inertia rotor makes these proven motors highly dynamic, and the latest winding and magnet technology means the motors are very compact," Ballard adds. "Reliability and ease of use are ensured with standard features such as KTY thermal sensors and plug connectors."
The low-backlash PSC planetary gear units have highly efficient wear-free gears and heavy-duty bearings and housings, giving these units high torsional rigidity and high overhung load capacity. "This, along with lifetime lubrication, means long, maintenance-free life," Ballard says. "The PSC's integrated input adapter accepts the CMP motor to form a compact servo gearmotor with simple, perfect fit and alignment without the use of external couplings. The variety of output flange and shaft options allows OEMs to use the same platform to fit many different mechanical situations."
Ballard says the new smart servo package saves OEMs time in selection, installation and startup, because the package is made up of components designed to do exactly that. "Scalable controls mean scalable costs," he explains. "And single-source supply from stock across the U.S. means that SEW stands behind the package, not just the parts."