PTS Data Center Solutions - White Paper Archives

WP -1 V5 The different types of UPS systems
There is much confusion in the marketplace about the different types of UPS systems and their characteristics. Each of these UPS types is defined, practical applications of each are discussed, and advantages and disadvantages are listed. With this information, an educated decision can be made as to the appropriate UPS topology for a given need. PDF 195 KB

WP -3 V0 Calculating Total Power Requirements for Data Centers
Part of data center planning and design is to align the power and cooling requirements of the IT equipment with the capacity of infrastructure equipment to provide it. This paper presents methods for calculating power and cooling requirements and provides guidelines for determining the total electrical power capacity needed to support the data center, including IT equipment, cooling equipment, lighting, and power backup. PDF 583 KB

WP -4 V4 Essential Power System Requirements for Next Generation Data Centers
Effective mission critical installations must address the known problems and challenges relating to current and past data center designs. This paper presents a categorized and prioritized collection of power system challenges and requirements as obtained through systematic user interviews. PDF 173 KB

WP -5 V3 Essential Cooling System Requirements for Next Generation Data Centers
Effective mission critical installations must address the known problems and challenges relating to current and past data center designs. This paper presents a categorized and prioritized collection of cooling system challenges and requirements as obtained through systematic user interviews. PDF 180 KB

WP -6 V2 Determining Total Cost of Ownership for Data Center and Network Room Infrastructure
An improved method for measuring Total Cost of Ownership of data center and network room physical infrastructure and relating these costs to the overall Information Technology infrastructure is described, with examples. The cost drivers of TCO are quantified. The largest cost driver is shown to be unnecessary unabsorbed costs resulting from the oversizing of the infrastructure. PDF 197 KB

WP -7 V2 Essential Rack System Requirements for Next Generation Data Centers
Effective mission critical installations must address the known problems and challenges relating to current and past data center designs. This paper presents a categorized and prioritized collection of rack system challenges and requirements as obtained through systematic user interviews. PDF 189 KB

WP -8 V1 Inter-System Ground Noise: Causes and Effects
Many power-related problems are the result of Inter-System Ground Noise. This problem cannot be corrected using typical AC-only power protection equipment. The cause and solution of Inter-System Ground Noise problems are described. PDF 272 KB

WP -9 V1 Common Mode Susceptibility of Computers
This Technical Note examines and challenges the claims made in literature regarding the alleged high susceptibility of computers to common mode noise. PDF 269 KB

WP -10 V1 Preventing Data Corruption in the Event of an Extended Power Outage
Despite advances in computer technology, power outages continue to be a major cause of PC and server downtime. Protecting computer systems with Uninterruptible Power Supply (UPS) hardware is part of a total solution, but power management software is also necessary to prevent data corruption after extended power outages. Various software configurations are discussed, and best practices aimed at ensuring uptime are presented. PDF 277 KB

WP -11 V0 Explanation of Cooling and Air Conditioning Terminology for IT Professionals
As power densities continue to increase in today's data centers, heat removal is becoming a greater concern for the IT professional. Unfortunately, air conditioning terminology routinely used in the cooling industry is unnecessarily complicated. This complexity makes it difficult and frustrating for IT professionals to specify cooling requirements and even makes it difficult to discuss current cooling system performance with contractors, engineers, and maintenance personnel. This paper explains cooling terms in common language, providing an essential reference for IT professionals and data center operators. PDF 197 KB

WP -12 V0 Essential NCPI Service Requirements for Next Generation Data Centers
Data Centers are a significant investment to the corporations and IT departments who they serve. Whether or not they actually achieve the availability of the design is highly dependent on the quality of the service personnel and their ability to meet the challenges specific to data center management. This paper presents a categorized and prioritized collection of those service challenges and the requirements needed to overcome them. It is based on information obtained in systematic interviews with data center clients and users. PDF 176 KB

WP -13 V0 Experts speak on UPS output Watt, VA, and Power Factor ratings.
Experts speak on the subject of UPS output ratings, and how the use of UPS with an output power factor rating of 1 reduces uncertainty of overloading the power system. PDF 31 KB

WP -14 V0 Essential NCPI Management Requirements for Next Generation Data Centers
The management of physical infrastructure in data centers can no longer be considered independently of the IT management architecture. In order to manage rapid change and achieve demanded levels of availability while controlling Total Cost of Ownership, IT managers can no longer afford to rely on the primitive, customized management solutions of the past. These solutions are no longer effective and must be replaced by systems based on, and integrated with, open IT management standards. With this in mind, this paper describes the requirements for management of next-generation Network-Critical Physical Infrastructure from the perspective of the ITIL framework. PDF 212 KB

WP -15 V0 Watts and Volt-Amps: Powerful Confusion
This note helps explain the differences between Watts and VA and explains how the terms are correctly and incorrectly used in specifying power protection equipment. PDF 25 KB

WP -16 V0 Protection of RS-232 Serial Connections
This Technical Note explains the special power protection issues related to RS-232 cabling. First, the special vulnerabilities of RS-232 cabling are explained. Then appropriate protection and mitigation techniques are provided. PDF 129 KB

WP -17 V0 Understanding Power Factor, Crest Factor, and Surge Factor
This White paper explains the technical terms of Power Factor, Crest Factor, and Surge Factor. The use of these terms in specifying UPS is explained. PDF 27 KB

WP -18 V0 The Seven Types of Power Problems
Many of the mysteries of equipment failure, downtime, software and data corruption, are often the result of a problematic supply of power. There is also a common problem with describing power problems in a standard way. This white paper will describe the most common types of power disturbances, what can cause them, what they can do to your critical equipment, and how to safeguard your equipment, using the IEEE standards for describing power quality problems. PDF 199 KB

WP -19 V0 Re-examining the Suitability of the Raised Floor for Data Center Applications
The circumstances that gave rise to the development and use of the raised floor in the datacenter environment are examined. Many of the reasons for the raised floor no longer exist, and the problems associated with raised floors suggest that their widespread use is no longer justified or desirable for many applications. PDF 184 KB

WP -21 V0 Neutral Wire Facts and Mythology
This Technical Note discusses many common misunderstandings about the function of the neutral wire and its relation to power problems. The subjects of dedicated lines, phase reversal, isolation transformers, and grounding are addressed. Various myths are described and criticized. PDF 54 KB

WP -22 V1 Understanding Emergency Power Off (EPO)
Emergency Power Off (EPO) is the capability to power down a piece of electronic equipment or an entire installation from a single point by activating a push button. EPO is employed in many applications such as industrial, telecommunications, information technology (IT), etc. This white paper describes the use of EPO for protecting data centers and small IT equipment rooms containing UPS systems. Various applicable standards that require EPO are discussed. Recommended practices are suggested for the use of EPO with UPS systems. PDF 330 KB

WP -23 V0 Reliability Models for Electric Power Systems
This note explains the sources of downtime in Electric Power Systems and provides an explanation for site-to-site variations in Power Availability. The the factors affecting power quality from generation to the utilization point are summarized. There is a qualitative description of a model which can be combined with data to provide a method for estimating down time based on site-related factors. PDF 29 KB

WP -24 V2 Effect of UPS on System Availability
This note explains how system availability and up-time are affected by AC power outages and provides quantitative data regarding up-time in real-world environments, including the effect of UPS on up time. PDF 101 KB

WP -25 V1 Calculating Total Cooling Requirements for Data Centers
This document describes how to estimate heat output from Information Technology equipment and other devices in a data center such as UPS, for purposes of sizing air conditioning systems. A number of common conversion factors and design guideline values are also included. PDF 205 KB

WP -26 V0 Hazards of Harmonics and Neutral Overloads
This document provides an overview of problems related to harmonic currents, with a specific focus on Information Technology equipment. The way that international regulations solved these problems is described. PDF 34 KB

WP -27 V1 Use of 208V vs 120V for Servers
This note explains why and when 208V is used instead of 120V for servers in North America. This same discussion applies to the use of 200V vs 100V in Japan. PDF 26 KB

WP -29 V4 Rack Powering Options for High Density
Alternatives for providing electrical power to high density racks in Data Centers and Network Rooms are explained and compared. Issues addressed include quantity of feeds, single-phase vs. three-phase, number and location of circuit breakers, overload, selection of plug types, selection of voltage, redundancy, and loss of redundancy. The need for the rack power system to adapt to changing requirements is identified and quantified. Guidelines are defined for rack power systems that can reliably deliver power to high density loads while adapting to changing needs. PDF 324 KB

WP -30 V10 Battery Technology for Data Centers and Network Rooms: Battery Options
The lead-acid battery is the predominant choice for Uninterruptible Power Supply (UPS) energy storage. Over 10 million UPSs are presently installed utilizing Flooded, Valve Regulated Lead Acid (VRLA), and High Density Modular Battery Cartridges (HDBCMBC) systems. This paper discusses the advantages and disadvantages of these three battery technologies. PDF 231 KB

WP -31 V5 Battery Technology for Data Centers and Network Rooms: Safety Codes
Fire safety regulations and their application to UPS battery installations are reviewed. In some cases, fire codes do not clearly recognize improvements in battery safety resulting from changing battery technology. Valve Regulated Lead Acid (VRLA) batteries are frequently deployed within data centers and network rooms without the need for the elaborate safety systems that are required for Vented (Flooded) Lead Acid batteries. Proper interpretation of the fire codes is essential in the design and implementation of data centers and network rooms. PDF 34 KB

WP -32 V5 Battery Technology for Data Centers and Network Rooms: Environmental Regulations
While most commercial battery back-up systems fall below government-required reporting levels, very large UPS and DC plant batteries may have to comply. Failure to comply can result in costly penalties. For lead acid batteries, environmental compliance focuses on the amount of sulfuric acid and lead at a particular location. Power ratings for VRLA batteries and modular battery cartridges are much higher than for flooded batteries at the same reporting threshold. This paper gives a high level summary of the regulations and guides the reader to sources of full information. PDF 256 KB

WP -33 V3 Battery Technology for Data Centers and Network Rooms: Site Planning
The site requirements and costs for protecting information technology and network environments are impacted by the choice of UPS battery technology. This paper will discuss how battery technologies impact site requirements. PDF 162 KB

WP -34 V1 Battery Technology for Data Centers and Network Rooms: Ventilation
Lead-acid batteries are the most widely used method of energy reserve. Ventilation systems must address health and safety as well as performance of the battery and other equipment in a room. Valve Regulated Lead Acid (VRLA) batteries and modular battery cartridges (MBC) do not require special battery rooms and are suitable for use in an office environment. Air changes designed for human occupancy normally exceed the requirements for VRLA and MBC ventilation. Vented (flooded) batteries, which release hydrogen gas continuously, require a dedicated battery room with ventilation separate from the rest of the building. This paper summarizes some of the factors and codes to consider when selecting and sizing a ventilation system for a facility in which stationary batteries are installed. PDF 52 KB

WP -35 V2 Battery Technology for Data Centers and Network Rooms: Lifecycle Costs
The lifecycle cost of different UPS battery technologies is compared. The costs associated with the purchase of batteries, the infrastructure costs, and the costs associated with inflexibility to meet changing requirements are discussed and quantified. PDF 41 KB

WP -37 V4 Avoiding Costs From Oversizing Data Center and Network Room Infrastructure
The physical and power infrastructure of data centers and network rooms is typically oversized by more than 100%. Statistics related to oversizing are presented. The costs associated with oversizing are quantified. The fundamental reasons why oversizing occurs are discussed. An architecture and method for avoiding oversizing is described. PDF 45 KB

WP -38 V0 Harmonic Currents in the Data Center: A Case Study
This document provides an overview of how problems related to harmonic neutral currents are mitigated by load diversity, with specific focus on Information Technology data center environments. Detailed measurements of an actual operating data center are presented. This case study illustrates the way that load diversity mitigates harmonic current levels, lowers shared neutral current in multi-wire feeders and branch circuits, and improves total circuit power factor. PDF 98 KB

WP -39 V1 Battery Technology for Data Centers and Network Rooms: VRLA Reliability and Safety
The Valve Regulated lead-Acid (VRLA) battery is the predominant choice for small and medium-sized Uninterruptible Power Supply (UPS) energy storage. This white paper explores how the technology affects overall battery life and system reliability. It will examine the expected performance, life cycle factors, and failure mechanisms of VRLA batteries. PDF 98 KB

WP -40 V1 Cooling Audit for Identifying Potential Cooling Problems in Data Centers
The compaction of Information Technology equipment and simultaneous increases in processor power consumption are creating challenges for data center managers in ensuring adequate distribution of cool air, removal of hot air and sufficient cooling capacity. This paper provides a checklist for assessing potential problems that can adversely affect the cooling environment within a data center. PDF 456 KB

WP -42 V1 Ten Steps to Solving Cooling Problems Caused by High-Density Server Deployment
High-density servers present a significant cooling challenge. Vendors are now designing servers that can demand over 20 kW of cooling per rack. With most data centers designed to cool an average of no more than 2 kW per rack, innovative strategies must be used for proper cooling of high-density equipment. This paper provides a ten-step approach for increasing cooling efficiency, cooling capacity, and power density in existing data centers. PDF 789 KB

WP -43 V2 Dynamic Power Variations in Data Centers and Network Rooms
The power requirement required by data centers and network rooms varies on a minute by minute basis depending on the computational load. This magnitude of this variation has grown and continues to grow dramatically with the deployment of power management technologies in servers and communication equipment. This variation gives rise to new problems relating to availability and management. PDF 176 KB

WP -44 V1 Improving Rack Cooling Performance Using Blanking Panels
Unused vertical space in open frame racks and rack enclosures creates an unrestricted recycling of hot air that causes equipment to heat up unnecessarily. The use of blanking panels can reduce this problem. This paper explains and quantifies the effects of blanking panels on cooling system performance. PDF 309 KB

WP -46 V4 Cooling Strategies for Ultra-High Density Racks and Blade Servers
Rack power of 10kW per rack or more can result from the deployment of high-density information technology equipment such as blade servers. This creates difficult cooling challenges in a data center environment where the industry average rack power consumption is under 2kW. Five strategies to cope with ultra-high power racks are described, covering practical solutions for both new and existing data centers. PDF 398 KB

WP -48 V0 Comparing Availability of Various Rack Power Redundancy Configurations
Transfer switches and dual-path power distribution to IT equipment are used to enhance the availability of computing systems. Statistical availability analysis techniques suggest large differences in availability are expected between the various methods commonly employed. This paper examines various electrical architectures for redundancy that are implemented in today's mission-critical environments. The availability analyses of these various scenarios are then performed and the results are presented. The analysis identifies which approach provides the best overall performance, and how alternatives compare in performance and value. PDF 295 KB

WP -49 V0 Avoidable Mistakes that Compromise Cooling Performance in Data Centers and Network Rooms
Avoidable mistakes that are routinely made when installing cooling systems and racks in data centers or network rooms compromise availability and increase costs. These unintentional flaws create hot-spots, decrease fault tolerance, decrease efficiency, and reduce cooling capacity. Although facilities operators are often held accountable for cooling problems, many problems are actually caused by improper deployment of IT equipment outside of their control. This paper examines these typical mistakes, explains their principles, quantifies their impacts, and describes simple remedies. PDF 240 KB

WP -50 V0 Cooling Solutions for Rack Equipment with Side-to-Side Airflow
Equipment with side-to-side airflow presents special cooling challenges in the modern data center. Common rack enclosures and rack layouts are fundamentally incompatible with side-to-side cooling, resulting in equipment that receives supply air of excessive temperature. This paper describes the problem along with several side-effects that are not generally appreciated. Various solutions to the problem are described along with their costs and benefits. PDF 732 KB

WP -55 V1 Air Distribution Architecture for Mission Critical Facilities
There are nine basic ways to use air to cool equipment in data centers and network rooms. These methods vary in performance, cost, and ease of implementation. These methods are described along with their various advantages. The proper application of these cooling techniques is essential knowledge for Information Systems personnel as well as Facilities Managers. PDF 594 KB

WP -56 V2 How and Why Mission-Critical Cooling Systems Differ From Common Air Conditioners
Today's technology rooms require precise, stable environments in order for sensitive electronics to operate optimally. Standard comfort air conditioning is ill suited for technology rooms, leading to system shutdowns and component failures. Because precision air conditioning maintains temperature and humidity within a very narrow range, it provides the environmental stability required by sensitive electronic equipment, allowing your business to avoid expensive downtime. PDF 312 KB

WP -57 V1 Fundamental Principles of Air Conditioners for Information Technology
Every Information Technology professional who is responsible for the operation of computing equipment needs to understand the function of air conditioning in the data center or network room. This introductory paper explains the function of basic components of an air conditioning system for a computer room. The concepts presented here are a foundation for allowing IT professionals to successfully specify, install, and operate critical facilities. PDF 338 KB

WP -58 V0 Humidification Strategies for Data Centers and Network Rooms
The control of humidity in Information Technology environments is essential to achieving high availability. This paper explains how humidity affects equipment and why humidity control is required. Quantitative design guidelines for existing and new computing installations are discussed. Alternative methods to achieve desired humidity are described and contrasted. The difficult issue of how and where humidity should be measured is explained. The hidden costs associated with over-humidification are described. PDF 262 KB

WP -59 V0 The Different Types of Air Conditioning Equipment for IT Environments
Cooling equipment for an IT environment can be implemented in 10 basic configurations. The selection of the appropriate configuration for a particular installation is affected by the existing facility infrastructure, the total power level of the installation, the geographical location, and the physical constraints of the building. This document describes the 5 fundamental cooling transport methods that combine with 2 fundamental physical arrangements to give rise to the 10 basic configurations. A method for selection of the appropriate configuration for a particular installation is described. The information in this paper allows IT professionals to be more involved in the specification of precision cooling solutions that better align with IT objectives. PDF 1310 KB

WP -60 V0 Avoiding AC Capacitor Failures in Large UPS Systems
Most AC power capacitor failures experienced in large UPS systems are avoidable. Capacitor failures can give rise to UPS failure and can in some cases cause critical load drops on stand-alone and paralleled systems. AC capacitor failures have historically been ascribed to unavoidable random failure or supplier defect. However, recent advances in the science of capacitor reliability analysis show that capacitor failures can be controlled by system design. This paper explains AC capacitor failure mechanisms and demonstrates how UPS designers and specifiers can avoid most common AC capacitor failures and the associated consequences. PDF 117 KB

WP -62 V0 Powering Single-Corded Equipment in a Dual Path Environment
The use of dual power path architecture in combination with IT equipment with dual power supplies and power cords is an industry best-practice. In facilities using this approach there are inevitably some IT devices which have only a single power cord. There are a number of options for integrating single-corded devices into a high availability dual path data center. This paper explains the differences between the various options and provides a guide to selecting the appropriate approach. PDF 482 KB

WP -63 V1 AC vs DC for Data Centers and Network Rooms
The use of DC power distribution as an alternative to AC in data centers and network rooms is uncommon. The considerations for the use of DC are described, and the reasons why AC will be the dominant choice for data center and network room power are explained. PDF 27 KB

WP -64 V1 Alternative Power Generation Technologies for Data Centers and Network Rooms
Fuel Cells and Micro Turbines are new technology alternatives for power generation for data centers and network rooms. This paper discusses the various modes of operation of these systems and examines benefits and drawbacks of the technologies when contrasted with conventional alternatives such as standby generators. PDF 54 KB

WP -69 V0 Power and Cooling for VoIP and IP Telephony Applications
Voice Over IP (VoIP) deployments can cause unexpected or unplanned power and cooling requirements in wiring closets and wiring rooms. Most wiring closets do not have uninterruptible power available, and they do not provide the ventilation or cooling required to prevent equipment overheating. Understanding the unique cooling and powering needs of VoIP equipment allows planning for a successful and cost effective VoIP deployment. This paper explains how to plan for VoIP power and cooling needs, and describes simple, fast, reliable, and cost effective strategies for upgrading old facilities and building new facilities. PDF 597 KB

WP -73 V0 Reducing the Hidden Costs Associated with Upgrades of Data Center Power Capacity
Scaling the power capacity of legacy UPS systems leads to hidden costs that may outweigh the very benefit that scalability intends to provide. A scalable UPS system provides a significant benefit to the Total Cost of Ownership (TCO) of data center and network room physical infrastructure. This paper describes the drawbacks of scaling legacy UPS systems and how scalable rack-based systems address these drawbacks. The cost factors of both methods are described, quantified and compared. PDF 165 KB

WP -75 V1 Comparing UPS System Design Configurations
There are five main UPS system design configurations that distribute power from the utility source of a building to the critical loads of a data center. The selection of the appropriate configuration for a particular application is determined by the availability needs, risk tolerance, types of loads in the data center, budgets, and existing infrastructure. The five configurations are explained, and advantages and disadvantages of each are discussed. The impact on availability is addressed for each configuration and guidelines are provided for choosing the appropriate design. PDF 339 KB

WP -76 V0 Modular Systems: The Evolution of Reliability
Nature proved early on that in complex systems, modular designs are the ones that survive and thrive. An important contributor to this success is the critical reliability advantage of fault tolerance, in which a modular system can shift operation from failed modules to healthy ones while repairs are made. In data centers, modular design has already taken root in new fault tolerant architectures for servers and storage systems. As data centers continue to evolve and borrow from natures blueprints, IT reliability analysis must also evolve to understand new strategies for survival, recovery, and growth. PDF 1019 KB

WP -78 V0 Mean Time Between Failure: Explanation and Standards
Mean Time Between Failure is a reliability term used loosely throughout many industries and has become widely abused in some. Over the years the original meaning of this term has been altered which has led to confusion and cynicism. MTBF is largely based on assumptions and definition of failure and attention to these details are paramount to proper interpretation. This paper explains the underlying complexities and misconceptions of MTBF and the methods available for estimating it. PDF 238 KB

WP -79 V0 Technical comparison of On-line vs. Line-interactive UPS designs
UPS systems below 5000VA are available in two basic designs: line-interactive or double-conversion on-line. This paper describes the advantages and disadvantages of each topology and addresses some common misconceptions about real-world application requirements. PDF 279 KB

WP -80 V0 Local versus Network Power for Cable Telephony
The customer premises network interfaces for cable-based telephony services require continuous power. In many cases the existing cable network is not configured to supply the needed power. The choices are to provide the power by upgrading the network power system, or to provide local power at each site. This paper describes the features and benefits of these alternatives and summarizes the factors that guide the selection between network and local power. PDF 52 KB

WP -81 V0 Site Selection for Mission Critical Facilities
When selecting a new site or evaluating an existing site, there are dozens of risk factors that must be considered if optimal availability is to be obtained. Geographic, site-related, building, and economic risks need to be understood and mitigated to lessen the downtime effects on your business. In this paper guidelines are established for selecting a new site or assessing an existing one. Common risks that affect the availability of a business are defined and techniques for minimizing these risks are presented. PDF 1071 KB

WP -82 V1 Physical Security in Mission Critical Facilities
Physical security controlling personnel access to facilities is critical to achieving data center availability goals. As new technologies such as biometric identification and remote management of security data become more widely available, traditional card-and-guard security is being supplanted by security systems that can provide positive identification and tracking of human activity in and around the data center. Before investing in equipment, IT managers must carefully evaluate their specific security needs and determine the most appropriate and cost-effective security measures for their facility. This paper presents an overview of the principles of personnel identification and describes the basic elements and procedures used in security systems. PDF 337 KB

WP -83 V0 Mitigating Fire Risks in Mission Critical Facilities
This paper provides a clear understanding of the creation, detection, suppression and prevention of fire within mission critical facilities. Fire codes for Information Technology environments are discussed. Best practices for increasing availability are provided. PDF 907 KB

WP -84 V0 Network-Critical Physical Infrastructure for Enterprise Wireless LANs
Wireless LAN (WLAN) deployments can result in unexpected or unplanned power, cooling, management and security requirements. Most wiring closets do not have uninterruptible power supplies (UPS), and they do not provide adequate ventilation or cooling required to prevent equipment overheating. Understanding the unique Network-Critical Physical Infrastructure (NCPI) requirements of WLAN equipment allows planning for a successful and cost effective deployment. This paper explains how to plan for NCPI while deploying indoor WLANs in small, medium or large enterprise, with emphasis on power and cooling. Simple, fast, reliable, and cost effective strategies for upgrading old facilities or building new facilities are described. PDF 872 KB

WP -85 V0 Data Line Transient Protection
Electrical transients (surges) on data lines can destroy computing equipment both in the business and home office environments. Many users appreciate the risk of power surges but overlook data line surges. This white paper explains how transients are created, how they can have devastating effects on electrical equipment, and how surge suppression devices work to help protect against them. PDF 201 KB

WP -86 V0 Network-Critical Physical Infrastructure for Medical Imaging & Diagnostic Equipment
Medical imaging and diagnostic equipment (MIDE) is increasingly being networked to Picture Archiving and Communications Systems (PACS), Radiology Information Systems (RIS), Hospital Information Systems (HIS), and getting connected to the hospital intranet as well as the Internet. Failing to implement the necessary Network-Critical Physical Infrastructure (NCPI) can result in unexpected downtime, and safety and compliance issues, which translates into lost revenue and exposure to expensive litigations, negatively affecting the bottom line. This paper explains how to plan for NCPI when deploying medical imaging and diagnostic equipment, with emphasis on power and cooling. PDF 415 KB

WP -90 V0 Essential Standby Generator System Requirements for Next Generation Data Centers
Effective standby generator system installations must address the known problems and challenges relating to current and past designs. This paper presents a categorized and prioritized overview of generator system challenges and the requirements needed to overcome them. PDF 218 KB

WP -92 V0 Local Powering Solutions for Fiber To The Home (FTTH) Technology
This paper starts with an overview of the markets primary line (lifeline) powering issues, and follows with a discussion of the potential power problems that currently exist in today's marketplace. A review of the purpose for a battery back-up solution in the Fiber To The Home (FTTH) application will be followed by listing three powering options available to locally power the Optical Network Termination device (ONT) while briefly outlining the pros and cons of each available option. PDF 340 KB

WP -93 V0 Fundamental Principles of Generators for Information Technology
Every Information Technology professional who is responsible for the operation of computing equipment needs to ensure their data center or network room is prepared for extended utility power outages. Understanding the basic functions and concepts of standby generator systems helps provide a solid foundation allowing IT professionals to successfully specify, install, and operate critical facilities. This paper is an introduction to standby generators and subsystems that power a facility's critical electrical loads when the utility cannot. PDF 272 KB

WP -100 V0 Management Strategy for Network-Critical Physical Infrastructure
When choosing a management solution for the physical infrastructure of IT networks, management of individual devices is necessary in order to have visibility to the many data points required for the reliable operation of network-critical physical infrastructure (NCPI). Element management solutions offer the optimum approach as they manage a particular type of device and have the ability to assimilate and, more importantly, make manageable the large volume of data necessary for network availability. PDF 475 KB

WP -101 V0 Fundamental Principles of Network Security
Security incidents are rising at an alarming rate every year. As the complexity of the threats increases, so do the security measures required to protect networks. Data center operators, network administrators, and other data center professionals need to comprehend the basics of security in order to safely deploy and manage networks today. This paper covers the fundamentals of secure networking systems, including firewalls, network topology and secure protocols. Best practices are also given that introduce the reader to some of the more critical aspects of securing a network. PDF 1086 KB

WP -109 V0 Reliability Analysis of the APC Symmetra MW Power System
This paper is a quantitative reliability analysis of the APC Symmetra MW UPS performed by MTechnology, Inc. (MTech). In contrast to common MTBF calculations based on summing component failure rates, this study used techniques of Probabilistic Risk Assessment (PRA) to calculate the likelihood of over 680,000 potential failure modes. The mathematical method accounts for uncertainty in failure rates and component performance, and provides detailed guidance as to the contribution of each system component to the overall risk of failure. The study included an exhaustive analysis of the systems architecture, component selection, control system, manufacturing practices, and response to internal and external faults. The study also included a detailed review of APCs delta conversion online topology. PDF 141 KB

WP -111 V0 Reliability Analysis of the APC InfraStruXure Power System
The APC InfraStruXure product line offers an alternative architecture to the central UPS. MTechnology, Inc. used the techniques of Probabilistic Risk Assessment (PRA) to evaluate the reliability of the 40 kW InfraStruXure UPS and PDU with static bypass. The calculations considered the performance of the InfraStruXure in both ideal and real-world conditions. The study also compared the performance of the InfraStruXure architecture to that of a central UPS serving a hypothetical 500 kW critical load in a data center. The results showed that the InfraStruXure architecture was significantly less likely to suffer failure of all loads in the data center, and slightly less likely to experience failure in any one piece of IT equipment. This paper summarizes the key findings of MTechnology's quantitative risk assessment and discusses their implications for facility managers and designers. PDF 249 KB

WP -112 V0 Performing Effective MTBF Comparisons for Data Center Infrastructure
Mean Time Between Failure (MTBF) is often proposed as a key decision making criterion when comparing data center infrastructure systems. Misleading values are often provided by vendors, leaving the user incapable of making a meaningful comparison. When the variables and assumptions behind the numbers are unknown or are misinterpreted, bad decisions are inevitable. This paper explains how MTBF can be effectively used as one of several factors for specification and selection of systems, by making the assumptions explicit. PDF 297 KB

WP -113 V0 Electrical Efficiency Modeling for Data Centers
Conventional models used to estimate electrical efficiency of data centers are grossly inaccurate for real-world installations. Estimates of electrical losses typically are made by summing the inefficiencies of the various electrical devices, such as power and cooling equipment. This paper shows that the values commonly used for equipment inefficiency are quite inaccurate. A simple but effective means for modeling the efficiency of power and cooling equipment provides for much more accurate results. PDF 2050 KB

WP -115 V0 Accounting and Tax Benefits of Modular, Portable Data Center Infrastructure
Well-informed accounting treatment of Network-Critical Physical Infrastructure (NCPI) assets provides significant opportunities to contribute to improving the financial performance of a business, institution, or organization. Design and manufacturing improvements in modular, scalable UPS systems, power distribution units (PDUs), and computer room air conditioners have not only created technological benefits, but provide entirely new NCPI asset management opportunities with direct and measurable financial benefits. PDF 196 KB

WP -116 V0 Standardization and Modularity in Network-Critical Physical Infrastructure
Failure to adopt modular standardization as a design strategy for Network-Critical Physical Infrastructure (NCPI) is costly on all fronts: unnecessary expense, avoidable downtime, and lost business opportunity. Standardization and its close relative, modularity, create wide-ranging benefits in NCPI that streamline and simplify every process from initial planning to daily operation, with significant positive effects on all three major components of NCPI business value availability, agility, and total cost of ownership. PDF 551 KB

WP -117 V0 Network-Critical Physical Infrastructure: Optimizing Business Value
To stay competitive in today's rapidly changing business world, companies must update the way they view the value of their investment in Network-Critical Physical Infrastructure (NCPI). No longer are simply availability and upfront cost sufficient to make adequate business decisions. Agility, or business flexibility, and low total cost of ownership have become equally important to companies that will succeed in a global, ever-changing marketplace. PDF 964 KB

WP -120 V0 Guidelines for Specification of Data Center Power Density
Conventional methods for specifying data center density are ambiguous and misleading. Describing data center density using Watts / ft2 or Watts / m2 is not sufficient to determine power or cooling compatibility with high density computing loads like blade servers. Historically there is no clear standard way of specifying data centers to achieve predictable behavior with high density loads. An appropriate specification for data center density should assure compatibility with anticipated high density loads, provide unambiguous instruction for design and installation of power and cooling equipment, prevent oversizing, and maximize electrical efficiency. This paper describes the science and practical application of an improved method for the specification of power and cooling infrastructure for data centers. PDF 341 KB

WP -123 V0 Impact of High Density Hot Aisles on IT Personnel Work Conditions
The use of modern enclosed hot aisles to address increasing power densities in the data center has brought into question the suitability of working conditions in these hot aisle environments. In this paper, it is determined that the additional heat stress imposed by such high density IT environments is of minimal concern. PDF 383 KB

WP -125 V0 Strategies for Deploying Blade Servers in Existing Data Centers
Blade servers operate at power densities that exceed the power and cooling capacities of virtually all data centers. Installing blade servers in an existing data center creates a bewildering set of challenges and options. This paper explains how to evaluate the options and select the best power and cooling approach for a successful and predictable blade deployment. PDF 346 KB