Optimising energy efficiency of conveyors

In their White Paper, Schneider Electric considers the role of conveyor systems used in Industry and a practical approach to reducing costs.  They estimate that in the real world, one can estimate that nearly 60% of the conveyors, loaded or unloaded, are running continuously. The result is fixed energy consumption.

The White Paper takes a practical view of moving from fixed to variable costs through operational analysis, and the use of energy savings through a wise choice of operating mode, the use of energy compensation, soft starters and variable speed drives as smart ways to make significant savings on a conveying line.

The moving and transporting goods are part of the daily life of each individual. In manufacturing and distribution activities, it is very often the bottleneck for many problems. Handling influences both upstream and downstream machine productivity, and impacts on the work-in-progress.

Frequently, handling has an effect on the quality of the product and the judicious use of soft starters or variable speed drives reduces maintenance by limiting the electric and mechanical shocks.

With more than 2,5 million conveyors put in operation annually in the world, conveying is an important energy consumer. A change of control philosophy allows:

– increase the productivity by optimising the operating modes,

– reduce the energy needs and thus limit the exploitation costs.

Automated Handling

Handling consists in moving a load from one place to another one without alteration. Several solutions can be used, but despite their apparent disparity, they can be grouped in two main categories:

1. manually operated conveyors controlled by an operator,

2. automated devices in which we find the conveyors family.

In manufacturing industries or distribution of products, the second solution is essential as it enables users to reduce the handling costs offering faster movement whilst reducing the risk of damage.

DECENTRALISED AUTOMATION

For many manufacturers, the use of a centralised PLC or control architecture has been phased out in favour of totally decentralised architectures controlling limited zones. This architecture allows a greater flexibility, the autonomy of small production islands and an easier adaptation.

Decentralisation also allows modularity and the rationalisation of the conveyors, leading to a reduction of the design cost for the system supplier and acquisition cost for the user.

Savings are a major consideration when designing a conveying line. Due to the large number of conveyors, cost can easily be unacceptable and the return on investment may be problematic

The White Paper is available for download from Schneider Electric’s website and covers:

INDEX

– Executive summary

– Introduction

– Reducing expenses

– From fixed direct costs to variable direct costs

– Operation analysis

– Validation of the operating mode

– Energy savings

– Application example

– Fixed direct costs reduction

– Real power, reactive power, apparent power

– Ways to limit the reactive power

– Ways to decrease the real power

– The Schneider Electric answer

– The distributed control offer

– The Automation Function Blocks dedicated to machines

– Conclusion

– An optimized design

Download the White Paper from Schneider Electric

See Schneider energy saving soft starters and variable speed drives here