Selecting and designing a Uninterruptible Power Supply (UPS) consists of eight steps. These steps are: determining the need for an UPS, determining the purpose(s) of the UPS, determining the power requirements, selecting the type of UPS, determining if the safety of the selected UPS is acceptable, determining if the availability of the selected UPS is acceptable, determining if the selected UPS is maintainable, and determining if the selected Uninterruptible Power Supply UPS is affordable. The last four steps may require repeating if the UPS does not meet all of the requirements. This process does not and cannot provide a “cookbook solution.” Each facility has unique requirements for emergency and standby power. These requirements include the reliability of the prime power source, the nature of the work done, local and state regulations governing emergency power, etc. The process does not give a single solution that is applicable to all cases.

• Determine the general need for an UPS.
• Determine the purpose of the UPS.
• Determine the power requirements.
• Select the type of UPS.
• Determine if the safety of the selected UPS is acceptable.
• Determine if the availability of the selected UPS is acceptable.
• Determine if the selected UPS is maintainable.
• Determine if the selected UPS is affordable.

References: “Joint Departments of the Army, Uninterruptible Power Supply System Selection, Installation, and Maintenance for Command, Control, Communications, Computer, Intelligence, Surveillance, and Reconnaissance (C4ISR) Facilities, 31 May 2002.”