1. Structured Cabling Systems
CCS Commercial Overview - Session 1
Server Rack Strategies
9th January 2009
Paul Mathews MInstSMM
Global Channel Manager

2. Introduction to Servers
• A server hosts a mail server, management of files and printer resources
• The server offers security to a companies processing resources
• A server enables faster and efficient data processing
• Servers support data backup and security
• The server navigates traffic and supports operations for desktops and
desktop applications

3. Brief overview of Servers
• Tower servers offer inclusive server and storage solutions and are ideal for
small, remote and branch office environments
• Rack servers offer maximum computing power in compact, space saving
design and are ideal for data centres with external storage
• Blade servers offer maximum computing power in compact, space saving
design with advanced power and cooling
designs and are ideal for data centres
with external storage

4. Introduction to Server racks/cabinets
• A rack should hold and securely locate electronic
equipment
• A rack should provide organised routing of power
and communications cabling
• A rack should assist airflow and cooling of
network equipment
• A rack should provide aesthetically pleasing
construction
• Most popular racks are 42U (internal height) for
19” rack mount equipment, approx 2 metres tall
and 80cm – 120cm deep

5. Facts about Data Centres and Computer Rooms
• In the present day, servers are generating heat of around 2.5kW per rack
(approx 5 servers loaded), this is typically 750kW per sq m
• In the future, servers are expected to generate heat of up to 10kW as CPUs
become even more densely packed
• This impacts revenue costs of energy bills as CRAC units are used to
compensate the heat
• Energy efficiency can be improved by the choice of cabling, design and
routing

6. Facts about Data Centres and Computer Rooms
• On average – every $1 spent on hardware, an additional $0.50 is spent on
power and cooling, more than double the amount 5 years ago (www.idc.com)
• Data Centre managers claim power and cooling issues are the single largest
problem in the data centre (www.gartner.com)
• 48% of computer room LAN and data centre budget is being spent on energy,
an increase of 8% in 5 years (www.gartner.com)

7. Introduction to energy use
• Energy that is delivered by electrical utilities is expressed and charged for in
kWh; kilowatt hours
Examples
• If a heater is rated at 1000 watts (1 kilowatt) and that heater is on for one hour
then one kilowatt hour is used
• Using a 60 watt light bulb for one hour consumes 0.06 kilowatt hours of
electricity. Using a 60 watt light bulb for one thousand hours consumes 60
kilowatt hours of electricity.
• If a 100 watt light bulb is on for one hour per day for 30 days that is 30 days X
100/1000 = 3 kilowatt hours.

8. What does increased energy use mean?
• It’s not government green – new EU Code of Conduct legislation requirements
http://www.connectixcablingsystems.com/news/detail.cfm?item=76
• Increased energy costs for businesses and governments
• Increased emissions (inc. greenhouse gases and electricity generation)
• Increased strain on the National Grid
• Increased electricity demand
• Increased capital costs for expansion of computer rooms and data centres
• Increased capital costs for new computer room and data centre projects
DC = direct current
AC = alternating current
amps x volts x power factor = power Watts

9. Ventilation – 1kW of heat dissipation
• Small to medium sized computer
rooms within SMEs
• Standard inset perspex door
• Horizontal fan unit

10. Ventilation – 2kW of heat dissipation
• Ventilated rack and doors, horizontal fan unit
• Chilled air access through floor tile access
Ventilation – 2-6kW of heat dissipation
• Escalation policy should be implemented
• Increase floor tile vent size up to 75% open area These solutions will
Take the heat dissipation
• Replace floor tiles with fan assisted grate tiles
to approx. 6kW per rack
• Add specialist fan units to top and base of rack
• Install a cabinet with a rear door utilised as a fan unit

11. Ventilation – 6-20kW of heat dissipation
• Typically computer room areas within data
centres
• Specialised racks required with dedicated
chilled water supply
• Hot aisle and cold aisle floor design
• No airflow compromised by gaps within the racks
(see www.ashrae.org – Thermal Guidelines for
Data Processing Environments)
• Air gaps within racks sealed with brush strips
• Excessive gaps at side of rack sealed with air
dam kit

12. Energy Efficiency Best Practices
• Install blanking panels
• Coordinate CRAC Units
• Improve under floor airflow
• Implement hot and cold aisles
• Install sensors to monitor temperature
• Implement cold aisle or hot aisle containment Additional information can be
found in the Gartner report ‘How
• Raise the temperature in the data centre (ASHRAE)
to Save a Million Kilowatt Hours
to improve electrical use
in your Data Centre’
• Exploit ‘free cooling’
• Design new data centres and computer rooms using modular cooling

13. Power Supply
• Server racks need to be powered
- Europe typically specifies 32 Amp, 240 V
single phase feed
• x 2 feeds are required for redundancy and
back up purposes
• A dual 32 AMP feed is counted as supplying 32 Amps x 230 Volts = 7.36 kVA
• For loads above 7 kVA then a 3 phase feed can be used to deliver 22 kW
• Power cables need to be kept separate from data cables – see Connectix
guidelines for proximity subject to 16/32 Amp power feeds

14. Power Distribution
• The power is distributed by a unit of sockets through a Power Distribution Unit
(PDU)
• PDUs are responsible for providing clean/conditioned power to the racks internal
network equipment
• PDUs can also be utilised for:
Intelligent sequential start up
Automatic crossover switch between 2 supplies
Status and power usage reports (LED or IP managed system)
• If more than 1 server rack is operational, a separate circuit breaker for each rack
power supply will isolate power surges and spikes

15. Building Automation Systems
• Server racks must be secure and include a system to monitor environmental
conditions (temperature and humidity) through a central location (BAS)
• Rack sensor systems offer information on:
Temperature
Smoke
Water
Humidity
Access
Vibration
Airflow
Air quality (particles)

16. Server Rack Technical Articles
• The Ideal Server Cabinet – Connectix Article 6
http://www.connectixcablingsystems.com/library/detail.cfm?item=38
• Improving Cooling and Airflow – Connectix Article 14
http://www.connectixcablingsystems.com/library/detail.cfm?item=83

17. Connectix Technical Articles
• Log on to www.connectixcablingsystems.com for full access to our data
centre and high speed LAN support articles
• Log on to www.connectixcablingsystems.com/events for details of our Data
Centre Design Principle Seminars run in association with The IET
IET Endorsed
CIBSE Continuing
Training Professional Development BICSI Continuing Education Credits
provider

18. Thanks for your time.