Distributed drives simplify conveyor control

More than 1000 integrated geared motor / frequency inverter combinations from Nord Drivesystems are being used to ensure fast, reliable shipment in a package sorting facility operated by a French logistics service provider. In order to minimise wiring and installation time and cost, Nord installed distributed drives for the conveyor system that measures several thousand metres.

Each belt conveyor drive unit incorporates a frequency inverter, motor and helical bevel or worm gear unit. With a capacity of 30,000 packages per hour, the facility is said to be one of the most efficient distribution centres in Europe. Packages must be transported to the correct loading ramp within three minutes, which requires precise motor control and synchronisation. The compact, lightweight geared motors, which feature Unicase housings, are high-performance units and are therefore well suited to distributed installations and mobile use. The frequency inverters used in this application provide a wide range of functions as standard. Each is mounted directly on top of the motor's terminal box. This integrated design ensures EMC conformity and saves costs for shielded motor cables and control cabinets. The drives have an efficiency of more than 97 per cent, do not require external cooling and withstand mechanical influences as well as fluctuating supply voltages and rapid temperature changes.

In addition to IP55 models, IP66 versions are optionally available. Interface modules for Profibus DP, Interbus, EtherCAT, CANopen/DeviceNet and ASi enable users to connect the drives to communication networks. For distributed drive systems, Nord also provides optional function modules for demanding tasks that have previously required more costly servo systems - such as 'flying shear' applications. The latest generation of Nord's distributed drive systems is showcased at www.sk200e.de.