The benefits of spreading things out

As manufacturers and plant owners strive towards maximising savings and improving flexibility, decentralised control systems are escalating in popularity. Mirroring the modular design philosophy increasingly adopted for control and automation systems, decentralised motor control systems involve the relocation of power components, plus monitoring and speed control units, to strategic positions near or on the motor.

Though it’s not the latest thing, decentralised control systems can provide a number savings and technical advantages over centralised systems. Not only do they offer a deal more installation and future-proofing flexibility than traditional motor control centres, but also the option of distributed intelligence across the plant floor leading to overall cost savings of the system.

An obvious savings area is in the amount of cabling needed.

For a bottling line with 200 metres of conveyor and 50 off 0.75 kW motors, power cable used can be shrunk to 700 metres from 3,000 metres by a using a decentralised approach.

Another area is to do with control cabinets. These can be made smaller, with fewer components providing easy integration with industrial Ethernet control systems rather than hard wired I/O.

Programming is also made simpler. Instead of a large, complex central PLC needed to govern an entire machine, each field distributor contains “local intelligence” providing programming specific to the set of activities carried out by the machine module. The central PLC can be made smaller and hence less expensive.

Decentralised control systems consist of flexible and intelligent structures, with significantly reduced commissioning times, allowing manufacturers to iteratively improve processes in response to market trends. A high level of serviceability results from the ease of sectional isolation which can often avert a worst-case ‘total line’ shutdown scenario. In production processes with considerable manpower the subsequent reduction in downtime can be a key factor.

According to drive technology specialist SEW-EURODRIVE, total savings of up to 30 percent can be achieved compared to a centralised control system. One of the company’s decentralised drive solutions is the MOVIGEAR® Mechatronic drive system. The MOVIGEAR® is able to achieve energy savings up to 50 per cent, using a Super Premium Efficiency IE4 motor combined with highly efficient gearing and on-board drive electronics mounted in a common housing.

Large overall savings are achieved for new installations or retrofits due to less engineering time needed, fewer components and less wiring, smaller panels, simpler local PLCs, and faster installation, debugging and commissioning, combined the potential for energy savings.

A hygienic system design for the MOVIGEAR® is available for installations in harsh environments, such as the food and beverage industry. Made from aluminium alloy housing it reduces trapped debris and corrosion due to smooth housing design and HP200 surface finish.

For finding a reliable distributed control solution, it’s important to seek out a supplier with industrial experience, and equipment that was designed to cope with industrial environments.

To learn more about distributed control and the savings it can bring, call SEW-EURODRIVE on 03 9933 1000 or visit

Leave a Reply