Karl Lycett, Rittal UK's Product Manager for Climate Control, explains the importance of cabinet cooling and how IT equipment operates more reliably if kept at the right temperature.
The phrase "up-tim" is an oft-repeated phrase for IT professionals, reflecting the fact that a key measure of their success is service availability. Modern climate control systems support "up-tim" but to understand why, you first need to consider the impact of poor climate control in order to decide which equipment to employ to take an installation to the next level.
IT manufacturers are increasing performance capabilities with each new generation of technology, while also reducing footprint. This leads to the heat-load within racks rising. If this is left unchecked, notably after an upgrade, it risks causing significant harm to your IT systems. IT equipment is very sensitive and must be kept in a strict temperature range to perform to its full potential. Straying outside these limits will speed up aging, shorten its lifespan and ultimately increase costs.
Equipment that is exposed to higher temperatures will reduce output to the point where it may shut down if a high enough threshold is met. Not surprisingly, mission-critical equipment that ceases operating can have very serious consequences for a business; a production line error or loss of e-mail systems is expensive to correct and carries the risk of major reputational damage.
Users who have added additional equipment may find their cooling system has to work harder to maintain the status quo, which then leads to a spike in energy consumption as well as a reduction in the life of the cooling system.
Rittal's team can provide guidance on how even small improvements can make significant differences to the efficiency of a cooling system, as well as lower costs.
Unoccupied rack space can mean the resulting spare "˜U' is left vacant. This allows hot air to leak into the cold area of the rack, which in turn affects the overall efficiency of the cooling equipment, reducing the "˜Î"T' along with the overall cooling performance. The use of blanking strips can fill up the spare "˜U' and ensure separation.
The same principle applies anywhere cables enter the rack and within the space either side of the 19" angles. These points allow both hot and cold air to mix and permits ambient air into the rack. The application of brush strips to the roof and base plate still allows the installation of new cabling, while still ensuring an effective seal. Foam strips that can be modified to suit a gap provide a solid barrier to either side of the angles and prevent an air short-circuit.
If perforated doors are being used then the installation of aisle containment should be high on the priority list. This is a system of door and wall pieces which create a barrier between the warm air and the cool air. The layout is at the customer's discretion but a "˜Cold Aisle' creates a pocket of cold air which can be utilised by all racks in the vicinity, and the "˜Hot Aisle' is the opposite, in which the hot air from numerous racks is kept in one zone.
This system is practical, it is modular and suits existing installs. It can increase performance and reduce the energy consumption of existing cooling equipment, which may avoid the need for an upgrade.
1. Types of cooling
There are many types of systems, each suited to different applications. If the heat load is small then fans can draw air through the rack and perform the cooling.
As heat density increases, there is need for mechanical cooling which uses either a Direct eXpansion (refrigerant) circuit or a Cold Water product connected to a chiller. Both are known as "split systems". They have their product in the white space, delivering cold air but employ a condenser for DX or chiller for CW. This approach has limitations dependant on manufacturer as there are maximum distances that have to be adhered to prevent any issues with pressure etc.
The installation will require holes being drilled for pipework and electrical supplies for both parts of the system.
2. Future expansion
Installing a cooling unit which is only slightly larger than the current loading inevitably means additional costs when new servers are installed. Some manufacturers offer scalable products via the addition of extra fans which allow users to increase the output as needed to ensure that same temperature range is maintained.
The same point rings true if when a chiller is specified with insufficient room for growth. This leaves two options; either the chiller is replaced with a larger one or the chiller can master slave with other chillers, allowing users to purchase another small chiller to work in tandem.
Users should also plan for any scenario where the climate control shuts down, and the way to do this is by building-in redundancy. Quite simply, this means adding more units than is needed so that when a product breaks down or requires maintenance, the heat load can be managed through alternative systems.
There are a range of additions that can take the functionality of your IT equipment to the next level.
Data Centre Infrastructure Management Software (DCIM) is offered by many manufacturers and allows the user to visualise their white space and equipment. If a DCIM is used in tandem with connected climate control or power, it gives remote access for the IT manager to live temperatures, energy usage and other variables. If anything changes, the DCIM will issue an alert so the problem can be resolved before it causes any harm to your equipment.
If you have multiple users - for example, if other businesses rent your rack space - it can create security concerns. Nobody wants an unauthorised person pulling out wires so it's worth investing in a DCIM in conjunction with lockable racks to prevent unauthorised entry and alert staff to any issue before your equipment is compromised.
In summary, good initial planning and future-proofing installations can prevent higher costs and further disruptions for a business down the line.
Come to Rittal's Stand D510 at DCW (Excel, London, 11-12 March 2020) to find out how our industry-leading experts can help you deliver your climate control requirements and optimise your operational efficiency. Go to www.rittal.co.uk for more information.