Sparks Electrical News July 2019

STANDBY AND EMERGENCY POWER

14

NEW UPS 3M DELIVERS 99% ENERGY EFFICIENCY

LOAD SHEDDING CALLS FOR ESSENTIAL GENSET MAINTENANCE

B ack-up power supply such as gensets become critical during load shedding. It is important that such important equipment is maintained properly and serviced regularly in order to be able to cope with extended electricity outages. Genset failure due to a lack of proper maintenance poses a significant business risk. “What is your business risk if a genset goes down? Here, you are not only looking at protecting the value of your assets, but what does the genset actually support and protect? If it is a hospital or a financial services provider, the implications speak for themselves,” ASP Fire CEO Michael van Niekerk advises. The first issue to be taken into consideration in terms of genset upkeep is the fuel supply. This can range from an integral tank at the base of the genset to a 2 200 litre Bulk To Farm Tank (BTF), or merely a 210 litre drum. “Hence we have the presence of flammable liquids, especially in terms of refuelling and the possibility of any spillages,” van Niekerk points out. Another issue is to control the growth of vegetation around a genset, especially if it is located outside. “Very often we will have vegetation encroaching on a genset, which is tucked away somewhere as an afterthought. We have even seen corporate customers piling office equipment onto, and around, a genset,” van Niekerk reveals. The genset itself is a potential source of fire ignition due to the high temperatures of the manifold itself. If the genset is located internally, these temperatures can be considerable, especially in the absence of adequate ventilation. Another important issue is the necessity of proper maintenance. If an oil filter has not been screwed on tightly enough, for example, it can result in an oil leak. “If oil sprays onto a hot manifold as a result of this, a fire will erupt,” van Niekerk warns. Thereafter the temperature will build quickly to a point where entrance into such a room is well-nigh impossible. Companies and individuals often lack the correct fire- fighting equipment to deal with genset fires. For example, a dry-chemical fire extinguisher will douse the flames, but not cool down any hot surfaces. A carbon-dioxide fire extinguisher, on the other hand, might cool down South Africa lets out a sigh of relief as it enjoys a respite in load shedding, but is it a good thing? What is load shedding? Load shedding (blackout) is what the utilities (suppliers) do when the demand exceeds the supply. It is the rotational disconnec- tion of supply to some areas, so that the remaining ones are receiving a supply of acceptable quality. The alternative is all consumers would experience low voltage, or ‘brownouts’. Why is there load shedding? Load shedding is of- ten due to the consumption peak being higher than the production level, not uncommon during winter months. However, recent load shedding was due to the weakness in Eskom’s generation capability who have explained this by blaming the coal quality, stor- age systems, supply of diesel, rain and weather in general. These, and the real reasons, are all just aca- demic to the consumer who is suffering the conse- quence of ‘mismanagement’. With our aging infrastructure being poorly man- aged, we ask ourselves if the absence of blackouts is a good thing, or are we being supplied with damag- ing power conditions such as brownouts, over volt- age, power surges…? Whereas a ‘blackout’ is having no power, a ‘brown- out’ is a period of minutes, or even hours, of low volt- age (the opposite of surges and over-voltage). The name comes from the dimming ‘brown’ colour of one’s lights instead of the desired bright light. During brownouts your equipment is effectively required to do the same work with less power. Pumps and mo- tors are having to work harder, which over time will reduce their efficiency, thus shortening their operat- ing life and increasing the repair, maintenance and replacement bills. To reduce regular brownouts, a utility may adjust transformers/substations to supply a higher voltage. During the period of high demand, say when offices and factories are occupied during the day, the sup-

Schneider Electric’s standardised rigor- ous procedures, the UPS rolls into po- sition quickly and installation is simple. It features an intuitive display interface for easy configuration and monitoring and, with optional network management card, customers can monitor and man- age the UPS status remotely through Schneider Electric’s EcoStruxure IT cloud-based software suite. “Our EcoStruxure team is ready to offer advice and installation, as winter months loom, with the possibility of power outages,” concludes Senzere.

the overheated genset itself, but this can result in major damage to the equipment due to thermal shock. Gensets not only supply standby power, but are essential to the day-to-day operations of institutions such as financial services and medical care. Hospitals, for example, will often have back-up gensets, all located in the same room. If a fire breaks out in one genset, the rest of the equipment is immediately at risk. “Hence we recommend an automatic fire-suppression system for such environments. It is unmonitored equipment, with a high fire hazard owing to the presence of flammable liquids and combustible products, as well as electricity. The probability of something going wrong may be slim in the mind of the end user, but in the likelihood that it does, the consequences can be potentially disastrous, and even fatal,” van Niekerk stresses. The next best option is a clean-gas fire-suppression system. “The problem with gensets and the heat they produce is that the rooms they are located in are normally ventilated, which compromises the integrity of the enclosure. If you discharge a gas system in this environment, it is therefore not possible to maintain the concentration of that gas for a sufficient period to suppress the fire. This means that clean-gas systems are not ideal in these scenarios,” van Niekerk cautions. The third option is a water-mist fire-suppression system, which has the added environmental benefit of only using a minimal quantity of water, which is also far more cost- effective than the clean gases themselves necessary to recharge the system. “ In terms of regulations and specifications related to gensets, such enclosures are classified as D4, which implies certain minimum fire-proof requirements, including a specific fire rating for the walls. “If the gensets in a building are not located in a purpose-built room, and are stuck away in the basement located next to parked cars, for example, that is a clear violation of the regulations. This is also important for end users to bear in mind,” van Niekerk concludes. ply would be acceptable simply because it is being distributed over the high demand. However, when the industry shuts down for the night or weekend, the higher voltage continues to be supplied and any loads which are running at that time are being sub- jected to over voltage. The consumer is left with two options to overcome the brownout or over voltage supply, which is, dis- connecting the load during times of unstable supply or stabilising the supply to their sensitive equipment. As we don’t always know when the mains power supply is going to deteriorate, the installation of an Automatic Voltage Switcher (AVS) could be used to safely disconnect the load, reconnecting auto- matically when the power supply returns to within pre-determined safe limits or an Automatic Voltage Regulator/stabilizer (AVR), which will buck boost over/high voltage and boost low/brownout voltages keeping equipment running safely for longer. Using a voltage regulator will effectively extend the battery pack back-up of an inverter/UPS system, or in the case of a generator, it will reduce running costs. Enquiries: +27 (0)11 452 2169

SCHNEIDER ELECTRIC has added the new Easy UPS 3M, a 60-100 kVA (400 V) Uninterruptable Power Sup- ply (UPS), to its 3-Phase UPS family of products. It is easy to install, easy to use, and easy to service, providing business continuity for small and medium busi- nesses and making it an excellent fit in both the data centre space and in indus- trial environments. With an optimised footprint design and enhanced product features, Easy UPS 3M protects critical equipment in a multitude of physical environments from damage due to power outages, surges and spikes. The unit saves on Capex investment while delivering up to 99% efficiency in energy-saving ECO mode. Customers benefit from the in- cluded start-up service to ensure the Easy UPS 3M is properly and safely configured for best performance, reli- ability, safety and peace-of-mind. “With our latest 3-phase offer, Sch- neider Electric is better able to meet both customer needs and partner re- quirements in a wide range of industries, making it an excellent fit for small and medium businesses, data centres and manufacturing facilities,” says George Senzere, Pre Sales Manager Anglo- phone Secure Power. “Part of our En- ergy Month drive, the Easy UPS 3M fills a growing market need for a solution delivering power availability, reliability, manageability, quality and convenience. “This new offer is rugged, with a wide input voltage window and strong over- load protection, all in a compact foot- print. Designed and tested following

Enquiries: www.se.com/za

LOAD SHEDDING, A NECESSARY EVIL!

Enquiries: nick.allen@sollatek.co.za

SPARKS ELECTRICAL NEWS

JULY 2019