Electricity and Control April 2022

ENERGY MANAGEMENT + THE INDUSTRIAL ENVIRONMENT

Use industrial UPSs for industrial applications

Uninterrupted power supply units, or UPSs, are designed for specific applications, taking account of respective environmental conditions and performance demands. Here, Ivor Becks, Sales Specialist, UPS Systems, Southern Africa, at ABB South Africa highlights why a commercial UPS should never be used in an industrial application.

Ivor Becks, specialist in UPS systems at ABB South Africa.

M any process industries create harsh environments. Various factors, such as mechanical vibration and chemical vapour contamination, contribute to this. The latter can cause corrosion and high levels of dust (which can be corrosive and/or conductive) and allow for vermin ingress (rodents, reptiles, insects). Other factors that play a role include temperature extremes (both high and low), condensing humidity and reciprocating tilting actions (such as on board a ship or an oil rig), and more. For applications in harsh environments, an industrial UPS should be the automatic choice, due to higher safety levels, less risk of expensive downtime resulting from power failures, a longer lifespan and reduced servicing costs. Industrial processes are largely controlled by automa- tion and control systems (SCADA systems, distributed control systems, and PLCs), field instrumentation, motor control cabinets, variable speed drives, actuators and field communication systems, all of which require perfectly con- trolled power. To ensure continuous, safe operation of pro- duction processes in harsh environments, and emergency shutdown of potentially dangerous processes, it is critical that the power supply to these systems is continuous. Safety-critical systems In situations where human life could be threatened, systems controlling rail signalling, or disaster warnings, fire warnings, evacuation warnings, or emergency lighting, for example,

For industrial applications, UPSs can be customised to ensure technical compliance as may be required for specific operating environments.

trast, is designed to last a minimum of 15 years, operating at high loads and in harsh conditions. It is important to use the correct UPS for respective ap- plications. A commercial UPS is designed to operate in less aggressive environments – that is, temperature-controlled and free of dust, vibration, corrosion and vermin. For such applications, UPS designers can set the internal compo- nents of a commercial UPS to operate closer to their design limits. This assists in reducing the cost of manufacture. The lifespan of internal components in a commercial UPS installed in a harsh environment is likely to be far shorter than that of a UPS designed for industrial applications. Using a commercial UPS design in an industrial process could therefore result in premature, unplanned failure of the UPS, leading to costly downtime, loss of production and possible damage to equipment, which could concurrently give rise to unsafe or unstable conditions. Potential risk There are a number of risks associated with using an incor- rectly rated UPS that is not designed to cope with the stress- es under which it is expected to function. Commercial UPSs are not expected to perform under the same environmental conditions as UPSs designed for industrial applications.

require absolute security of electrical power for their operation. Such safety- critical systems must not fail because of the risks that would raise of injury and/or loss of life, as well as potentially substantial financial losses due to extensive plant damage and loss of production. Expected lifespan In a ‘controlled’ or ‘normal’ environment, a commer- cial UPS typically has a design life of ten years. An industrial UPS, by con-

Industrial UPSs incorporate the key attributes required for applications in manufacturing plants and industrial control rooms.

12 Electricity + Control APRIL 2022