Superdome Servers - I/O Expansion Cabinet Guide, Fifth Edition

Appendix B
Site Requirements
Power Requirements
205
Power Requirements
In general, a well-designed power distribution system exceeds the requirements of most electrical codes. A
good design, when coupled with proper installation practices, produces the most trouble-free operation.
A detailed discussion of power distribution system design and installation is beyond the scope of this
document. However, electrical factors relating to power distribution system design and installation must be
considered during the site preparation process.
The electrical factors discussed in this section are:
• Computer room safety
• Electrical load requirements (circuit breaker sizing)
• Power quality
• Distribution hardware
• System installation guidelines
Computer Room Safety
Inside the computer room, fire protection and adequate lighting (for equipment servicing) are important
safety considerations. Federal and local safety codes govern computer installations.
Fire Protection
The National Fire Protection Association’s Standard for the Protection of Electronic Computer Data
Processing Equipment, NFPA 75, contains information on safety monitoring equipment for computer rooms.
Most computer room installations are equipped with the following fire protection devices:
•Smoke detectors
• Fire and temperature alarms
• Fire extinguishing system
Additional safety devices are:
• Circuit breakers
• An emergency power cutoff switch
Lighting Requirements for Equipment Servicing
Adequate lighting and utility outlets in a computer room reduce the possibility of accidents during equipment
servicing. Safer servicing is also more efficient and, therefore, less costly.
For example, if there is not enough light, it is difficult to see cable connection points on the hardware.
Adequate lighting reduces the chances of connector damage when cables are installed or removed.
The minimum recommended illumination level is 70 foot-candles (756 lumens per square meter) when the
light level is measured at 30 inches (76.2 cm) above the floor.
Electrical Load Requirements (Circuit Breaker Sizing)
It is always a good idea to derate power distribution systems for one or more of the following reasons: