The case for solid-state switching

Abstract

In harsh manufacturing environment, the twin goals of minimising downtime and maximising productivity are vital for all companies. Not only is it necessary to maximise returns for shareholders, for many companies it is as simple as whether they stay in business or not. As part of this quest for improved productivity, OEMs and systems integrators are looking to push their machines and processes to ever-increasing speeds. In modern machinery applications (such as packaging, palletising or conveying), it would not be considered unusual to switch three-phase electric motors every second or so. Even under almost ideal operating conditions, and specifying high-quality products, the electrical life of an electromechanical contactor is typically exceeded in fewer than two million operations. At this point, the contactor would have to be replaced, resulting in lost production time and increased costs with respect to labour and replacement devices. The whole life cost, including machine downtime and repair, needs to be included in any calculations when it comes to making the decision between the solid state and the more traditional electro-mechanical contactor.