How to keep VFDs and motors running

  Applied to blowers and pumps, VFDs offer energy savings and, in mechanical applications, allow fine adjustments which are impossible with other methods. Yet they are not simple plug-in-and-forget devices. Variable frequency drives (VFDs) are full of electronics and are susceptible to many problems, from incoming power disturbances to environmental hazards and incorrect use – […]

Redundancy in ethernet communications for power utilities

  Ethernet has become, without a doubt, the standard for communications networks around the world, whether for utility, industrial, ITS or any other mission critical application. Moving to ethernet rather than the more traditional serial communications has changed the way that these sites and applications are being handled, the most obvious change being that the […]

Rectifier transformers: Technology update

  Industry sectors such as the electrochemical and smelting rely on low voltage high current DC supplies for operation, which are supplied from sources known as rectifier transformers. This article is an overview of the technology available in this field. The transformer and rectifier are provided as a combined unit. The low voltage and very […]

Monitoring large electric motor terminations prevents failure

  It is often the case that failure of the cheapest component can bring about failure of the whole system, and in many cases condition monitoring is applied effectively to larger system components but not as effectively to the less significant ones. In the case of large electric motors, failure of the terminations can result […]

Water desalination and energy

  Water takes a close second to energy as the commodity most under pressure in the future, and the least available. Energy can be produced, but the supply of fresh water is totally dependant on weather and climatic conditions. For this reason desalination of seawater is becoming an increasingly important factor in the fresh water […]

The importance of reliable control power

  Today’s power systems have the potential to be more reliable, easier to maintain and simpler to diagnose than ever before. This is made possible by the advent of microprocessors now available in everything from protective devices to programmable logic controllers (PLCs) to monitoring and diagnostic devices. While technology is rushing forward, the underlying implementation […]

Reliable power for data and telecommunications sites

  Fuel cells are finding increasing use in the ICT sector, both as back-up power and as primary power sources, and are proving to be an effective alternative to traditional battery and diesel generator backup systems, in a variety of applications, from small remote telecommunications sites, to large data centres. Fuel cell technology features both […]

Lightning and surge protection for rooftop PV systems

  According to the South African Photovoltaic Industry Association (SAPVIA), photovoltaic (PV) is the fastest growing power generation technology in the world. Between 2006 and 2009 the installed capacity globally grew on average by 60% per annum. These systems are exposed to all weather conditions and are expected to be able to withstand them over […]

Benefits of continuous improvement in energy management

  Using its own energy monitoring system, Endress and Hauser detected that the ventilation system of one of its buildings was using almost three times the energy of any other. As a result, the company starting looking for a method of improving its energy saving and efficiency programme at its production centre. In 2012, in […]

Industrial power and energy savings initiatives in South Africa

  The electricity crisis of 2008 sparked an unprecedented interest in electrical energy efficiency. In the previous era of the cheapest electricity in the world and an abundant supply, little attention was paid to efficiency of electricity usage. The crisis resulted in numerous initiatives by government, the utility, industry associations and consumers, all aimed at […]