23 Jul 2024


Distributed drives take centre stage at Hanover

Distributed drives take centre stage at Hanover

One inescapable trend at the recent Hanover Fair was the growing importance of distributed drive systems, which have the potential to cut installation times and costs and do away with the need for central control cabinets. Companies promoting technologies of this sort included Lenze, Moeller, Siemens and SEW Eurodrive.

Lenze is using a system developed by Insatronic, a joint venture company in which it took a 25% stake at the end of last year. The system includes time-saving elements such as prefabricated cables, plug-in terminals and automatic downloading of configuration data. Lenze says that the system will allow motor controls on conveyors to be replaced in under three minutes.

The Insatronic technology, which is already used in the automotive industry, links elements including Lenze`s motec inverters and starttec starters. Using the system, one motec inverter can be used to drive two different motors in applications where they do not need to operate at the same time. The motec inverters can handle loads from 0.25-7.5kW.

The starttec motor switches have been designed as a simple, cost-effective alternative to contactors, which also reduce starting currents. They cover the power range 0.25-4kW, and can be controlled via a fieldbus or using digital inputs and outputs.

Moeller`s distributed system, called Rapid Link, is targeted in particular at conveyor installations where is allows switching and protection components to be installed next to the motors. It consists of several modules including: inverters; starters (either direct-on-line or reversing) with electronic protection and covering ratings from 0.18-2.2kW; and disconnectors which combine a main switch, maintenance switch and cable protection in a single device. The modules can be replaced without interrupting the operation of a line.

AS-i connectors are built into the various Rapid Link modules but the system also includes a gateway that will link it to higher-level field buses.

A third option on show in Hanover was Ecofast, a system which Siemens has been developing with partners including SEW Eurodrive, Harting and Demag. They hope that it will become the de facto open standard for distributed drives.

The combination of Ecofast-compatible starters, inverters, distributed I/O and motors from Siemens, geared motors from SEW Eurodrive; and tee-connectors for signal and power cables from Harting, are said to allow the installation of complete distributed drive systems. Siemens claims that the cost of a decentralised installation will typically be 10-20% less than that of a system based on central control cabinets.

As well as the Ecofast hardware, Siemens is providing a software package that optimises an installation`s energy consumption. The user enters parameters such as motor ratings and cable lengths, and the graphical software calculates cable cross-sections and short-circuit currents. The power cable, with a cross-section up to 4mm2, can support several 400V motors connected in series. The Ecofast system uses Profibus-DP and AS-i for communications.

Pilot Ecofast systems have been installed in plants operated by Audi, DaimlerChrysler and Siemens.