Supplied by HiREf Supplied by Spoormaker & Partners Supplied by Spoormaker & Partners www . refrigerationandaircon . co . za RACA Journal I February 2024 19
Feature safeguard against physical breaches but also to maintain the confidentiality of the information stored within .”
HiRef ’ s pursuit of energy efficiency underscores the delicate balance between minimising the cooling system ’ s footprint and optimising efficiency . “ The challenge lies in reconciling the demand for compact systems with the need for efficient cooling , often resulting in a tug of war between conflicting requirements . Data centres tend to be measured in megawatts rather than square metres , there being a correlation between computing power and heat generation . For every kilowatt of computing power , an equivalent kilowatt of heat is produced . This necessitates robust cooling systems , often discussed in the context of larger coils for better efficiency but a larger footprint ,” says Koeslag .
IT SYSTEMS NEED CLEAN POWER HVAC systems play a critical role in ensuring the proper operation of data centres . By maintaining the correct temperature and humidity levels , HVAC systems are necessary to ensure the protection of IT equipment from damage caused by high temperature , dust or corrosion , and to enhance the reliability of data centre operations .
For instance , harmonics in electrical systems can have serious consequences , including reducing the life of equipment , causing stress on cables and equipment , and degrading the electrical system over time . Harmonics are generated by nonlinear electronic loads and can cause apparatus overheating , increase power and air conditioning costs , and reduce system efficiency in instances where there are hundreds of EC fans and LED lighting within a data centre .
To address this issue , Ziehl-Abegg has developed an active harmonic filter that measures harmonics fluctuation and cleans the power supply to prevent feedback , says Marius du Plessis , MD Ziehl-Abegg South Africa .
Typically , an air handling unit ( AHU ) has multiple fans due to the requirement for built-in redundancy .
“ OEMs will provide us with specifications such as a need for air flow at 30m3 a second at 800 pascals . Our system takes into account a worst-case scenario , requiring primary , secondary and sometimes HEPA filters , and maintaining the pressure of the interior a few pascals above the outside – to keep out dust and insulate the building .
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1 . Containerised data centre . 2 . Airflow around IT racks . 3 . Cooling cycle .
4 . ASHRAE data centres psychometric . 5 . HiRef HCB .
“ The fans are equipped with EC motors and built-in speed control , which allows for precise control of the fan speed and airflow . Ziehl-Abegg ’ s equipment can measure the flow and control the fans to the desired setpoint , ensuring that the IT equipment is operating at optimal temperature and airflow ,” says Du Plessis . To overcome the issue of dirty filters , Ziehl-Abegg designs the fan wall to accommodate the maximum dirty-filter pressure drop . The fan wall is designed to handle different types of
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Supplied by HiREf Supplied by Spoormaker & Partners Supplied by Spoormaker & Partners www . refrigerationandaircon . co . za RACA Journal I February 2024 19