classic | mobile
Follow us on:
Follow us on Facebook  Share via Twitter  Share via LinkedIn
 

Search...
Hi-Tech Security Solutions Business Directory
Residential Estate Security Handbook 2018


Essential backup power equipment
September 2017, This Week's Editor's Pick, Security Services & Risk Management, Residential Estate (Industry)

Planning for unexpected power outages has become an essential part of any security strategy. While the primary types of equipment available for supplying backup power haven’t change much in the last few years, continual technological advances mean that some equipment becomes more relevant than others, depending on the subtleties of their operation.

The UPS is the main backup power mainstay, and is differentiated between off-line and on-line models, as Eurobyte Technology’s Neal Thomas describes: “With an off-line UPS, as the name suggests, the inverter module is off-line and does not feed any power to the protected device. The batteries are however connected to the mains power so they stay charged at all times in the event that there is a power failure. Because the inverter module is not feeding power to the protected device, it is not protecting it from other power issues such as power spikes. Once the power goes off there is a slight delay for the inverter to respond, usually between 2 to 10 milliseconds which could adversely affect sensitive electronics.

“An on-line UPS is always on-line and acts as a buffer between the main power and the powered devices. This regulates the electrical flow from the mains to the devices, which also protects them in the event of power spikes and brownouts. Because this unit is always on-line it means there is no switchover time from the UPS once the mains go out and your electronic devices are not affected by any form of a switchover.

“Lastly we have the line interactive UPS, which uses bits of the technologies from both the off-line and on-line UPS. This allows it to function in the same way as an off-line UPS with the difference that it incorporates a voltage regulator which helps to protect devices from more than just power failures, but also against power spikes and brownouts which we experience frequently in South Africa.”

Legrand South Africa is another company that supplies UPSes and related backup power equipment, and the company’s Marius Labuschagne summarises the differences between on-line and off-line models by saying that “Generally on-line UPSes, unlike off-line alternatives, are expensive and inefficient as the inverter is continuously in operation, however it provides better quality of power as compared to an off-line UPS.”

Further exploring inverter technology, Labuschagne explains that the role of the inverter is to take the utility’s pure AC sine wave and convert it into DC in order to charge batteries. The DC is then rectified back into AC, and two main types of rectifiers are available for this step. “Firstly, square wave rectifiers are a cost effective solution to achieve AC. However, the voltage is not ramped on a smooth curve but instead is pulsed on and off at a frequency of 50 to 60 Hz, thus producing a square waveform. Though this technology works well for the majority of electrical goods, unfortunately certain electronics depend on a smooth sine wave and may not function correctly with the square wave.

“This brings us to the second type: the true or pure sign wave rectifier. The advanced electronics used in these are more costly, but the stable waveform offers high-end electronics and sensitive equipment a true, smoothly ramped sine wave.”

When it comes to longer-term power outages, a generator is the go-to solution, and should always be specified at a higher power rating than the UPS that is being used, according to Thomas. “The reason for this is that the generator is running to your devices through the UPS, so if you are using a generator that has a lower power rating you will still be running down the UPS battery and this could cause damage to your UPS, and in turn damage the electronic devices you are trying to power. Also keep in mind that the generator should have a built in voltage regulator to ensure that the power coming through is clean, so as not to damage the electronic devices – this is also where your choice of UPS becomes important.”

As Labuschagne explains it, “the UPS operates from charged batteries and, depending on the autonomy available, can offer a full load supply instantaneously as the mains fail. This gives the generator time to start up and ramp to the required load, at which point it will support the UPS by recharging in order to sustain power. The full UPS load on the generator should be around half to a maximum of two thirds of the full load capacity of the genset. The reason for this is that any switching of equipment on a generator running close to full load may cause dipping and ramping of voltages and frequency as the generator tries to compensate with little reserve. In order to avoid this fluctuation manufacturers recommend 50% to 70% operating loads on gensets.”

Petrol and diesel powered generators have long been the main contenders, but the use of gas generators is now becoming more common. Labuschagne summarises the main differences between the three options as follows: “Gas gensets are silent with clean combustion. They provide moderate power levels and are very expensive to buy, but the running costs are lower. Diesel units are more noisy and the combustion is not clean, however they are more powerful and cost effective to run. Petrol generators provide strong power output and versatility in application, but are less cost effective than diesel and a bit noisy.”

For more information contact:

• Neal Thomas, Eurobyte Technology, +27 (0)21 551 2804, neal@eurobyte.co.za, www.eurobyte.co.za.

• Marius Labuschagne, Legrand South Africa, +27 (0)11 444 7971, marius.labuschagne@legrand.co.za, www.legrand.co.za.


Credit(s)
  Share via Twitter   Share via LinkedIn      

Further reading:

  • ASIS Security Technology Concepts day
    April 2019, Technews Publishing, This Week's Editor's Pick, Security Services & Risk Management
    ASIS SA kicked the tyres of a few technologies at its first Security Technology Concepts day in February.
  • Securing a reliable source of backup power
    April 2019, Drensky Technologies, Mustek Security Technologies, Specialised Battery Systems, Security Services & Risk Management
    Dependence on a reliable and stable source of electrical power is a part of everyday life, whether for an individual or a business.
  • The value of having a maintenance contract or SLA
    April 2019, Johnson Controls, Mustek Security Technologies, Security Services & Risk Management
    A maintenance contract or SLA offers a company peace of mind regarding the functioning of their security installation.
  • Visible light facial recognition
    April 2019, ZKTeco, Technews Publishing, This Week's Editor's Pick, Access Control & Identity Management, Integrated Solutions
    ZKTeco recently expanded its reach in the facial recognition market with the launch of its new series of visible light facial recognition (VLFR) products.
  • 2019 Internet of Things (IoT) Barometer
    March 2019, This Week's Editor's Pick, Integrated Solutions, IT infrastructure
    A majority of businesses that use IoT technology agree that it has either disrupted their industry or will do so in the next five years.
  • When cybercrime affects health and safety
    April 2019, This Week's Editor's Pick, Cyber Security
    The threat of a category-one cyber-attack is that everything could seem right – the readings on the meter could be fine, checklists would be followed, and equipment would work – yet danger could still unfold.
  • Cathexis wraps up successful national roadshow
    April 2019, Cathexis Technologies, This Week's Editor's Pick, CCTV, Surveillance & Remote Monitoring, News, Conferences & Events, Training & Education
    Cathexis Technologies successfully concluded its national CathexisVision Roadshow. With events held in Durban, Port Elizabeth, Johannesburg and Cape Town.
  • Milestone Systems launches Milestone Marketplace
    April 2019, Milestone Systems, This Week's Editor's Pick
    Milestone Systems introduces Milestone Marketplace, a digital platform for the video technology industry that connects buyers and sellers to co-create solutions.
  • Biodegradable security seals for SA
    April 2019, TruSeal, This Week's Editor's Pick, Asset Management, EAS, RFID, News, Security Services & Risk Management
    The new TruSeal product extension is produced from a special biodegradable material sourced from Malaysia.
  • CCTV operators’ duties to response personnel at crime scenes
    April 2019, Leaderware, This Week's Editor's Pick, CCTV, Surveillance & Remote Monitoring, Security Services & Risk Management
    Control room operators often have a responsibility to monitor response scenes that go beyond the initial detection and response relationship.
  • Cyber/physical perils in hospitality
    April 2019, Wolfpack Information Risk, This Week's Editor's Pick, Cyber Security, Entertainment and Hospitality (Industry)
    How can we prepare for our holidays and avoid becoming the victim of a scam or data breach?
  • Better energy savings than BMS
    April 2019, Johnson Controls, Integrated Solutions, Security Services & Risk Management
    Central plant optimisation software provides better energy savings than BMS control alone.

 
 
         
Contact:
Technews Publishing (Pty) Ltd
1st Floor, Stabilitas House
265 Kent Ave, Randburg, 2194
South Africa
Publications by Technews
Dataweek Electronics & Communications Technology
Electronic Buyers Guide (EBG)

Hi-Tech Security Solutions
Hi-Tech Security Business Directory (HSBD)

Motion Control in Southern Africa
Motion Control Buyers’ Guide (MCBG)

South African Instrumentation & Control
South African Instrumentation & Control Buyers’ Guide (IBG)
Other
Terms & conditions of use, including privacy policy
PAIA Manual
         
    Mobile | Classic

Copyright © Technews Publishing (Pty) Ltd. All rights reserved.