Electronics Protection - Fall 2015 - (Page 8)

Feature Data Center Design and Cooling for Sensitive Electronics Marc Caiola, Global Category Director - IT/DATACOM Pentair/Schroff Processing power and the speed at which crucial data center infrastructure equipment runs is steadily increasing to keep up with user application demands. Through technology advances, the size of these electronics is shrinking, resulting in greater board population density and higher power consumption. This yields increased heat generation throughout the data center where equipment is housed and operated. All equipment must be kept below a specified temperature range, high heat levels can damage networking equipment and potentially eliminate a company's ability to effectively process, communicate and store information. Since nearly all power consumed by equipment processors is converted to heat, data center equipment must be effectively cooled to maintain maximum availability and operational efficiency. Implementing the proper cooling solution will not only protect data centers from costly damage, but also ensure continuous access to company data and communications in an economically and environmentally responsible way. Cooling solutions have become more sophisticated, providing new methods for improving cooling while enhancing overall efficiency to adapt to changing networking equipment and data center designs. Data center managers can select and implement the ideal solution that adequately addresses individual cooling requirements by understanding the evolution of modern cooling solutions, along with their advantages and disadvantages. Cubic Feet per Minute (CFM) Another way to increase the amount of heat dissipated or removed from network equipment is by increasing the airflow, expressed in CFM. An increase of CFM, the amount of airflow across a given area in a given time, results in increased heat removal. CFM can be achieved through the use of fans. The larger the fan, the more CFM it provides. An increase in RPM (the speed at which the fan circulates) as well as the size or quantity of fan blades results in a higher CFM, but as these factors increase, so do several others that can be detrimental to the data center equipment. For example, acoustic noise is one consequence of high levels of CFM. Additionally, at very high CFM, physical forces also come into play that can cause damage to electrical equipment. Plus, the higher the CFM, the higher the upfront capital costs, as well as ongoing operational expenses. Calculating Heat Dissipation Requirements When it comes to cooling a data center, one equation is key: Watts = 0.316 x CFM x ΔT. Whereas, Cold intake air and airflow (CFM) are both required to cool network equipment. These two factors work directly to dissipate the heat that network equipment produces. While increasing either factor will increase the amount of heat that is dissipated, there are limits. Air that is too cold results in thermal expansion and condensation issues. Airflow that is too high results in acoustic and physical limitations. A cooling system that relies on too much of only one of these factors usually results in higher capital and operating costs. Finding an ideal balance between cold air and airflow allows optimal heat dissipation, protecting network equipment from the consequences of overheating. Measured in degrees Fahrenheit, ΔT (Delta T) refers to the difference between equipment intake air and exhaust air. A greater temperature differential signifies more heat being removed. While it is difficult to constantly deliver the coldest air to all equipment, in particular equipment installed in upper rack units, ideal configurations maintain a range between 10°F and 30°F ΔT. 8 Fall 2015 * www.ElectronicsProtectionMagazine.com The data center must provide enough CFM to the equipment to prevent overheating. CFM in = CFM out Diverse Cabinet Level Cooling Configurations Cabinet configurations are available in a variety of options, ranging from simple and inexpensive to costly and complex. The goal of each configuration is the same: help deliver the necessary amount of cool air to each server in the most efficient means possible. Hot Aisle/Cold Aisle Hot aisle/cold aisle cooling systems are designed to separate hot exhaust from cold intake air. Cabinets located on both sides of the cold aisle draw cold air from perforated floor tiles and through their front intakes. Hot exhaust exits through cabinet rears and is directed to Computer Room Air Conditioning (CRAC)/ Computer Room Air Handler (CRAH) units, which remove the heat and redistribute air to the cold aisles. Playing a crucial role in airflow management, hot aisle/cold aisle configurations provide numerous benefits. By separating hot and cold air, the energy required to maintain the optimal data center temperature is minimized, allowing facilities to significantly reduce their utility costs. However, it is important for managers to understand that hot aisle/cold aisle designs are typically only able to accommodate heat dissipations between 3 to 5 kW. Once rack densities reach 5 kW and above, the system can no longer compensate for the increased heat loads. According to multiple http://www.ElectronicsProtectionMagazine.com

Table of Contents for the Digital Edition of Electronics Protection - Fall 2015

Electronics Protection - Fall 2015
Contents
Editor's Choice
Beat the Heat: Six Best Practices for Protecting Your People and Your Business from Arc Flash Hazards
Data Center Design and Cooling for Sensitive Electronics
Electronic Access Solutions - Design Considerations for Your Data Center
An Unsung Hero: the Gas Discharge Tube
Innovation Demands That You Break the Rules
Enclosures
Thermal
Power
Hardware
Industry News
Calendar of Events

Electronics Protection - Fall 2015