UPS (Uninterruptible Power Supply) Requirements
    
    
    
        A UPS (uninterruptible power supply) is a device that sits between a
            power supply (such as a wall outlet) and a device (such as a switch) to prevent outages,
            sags, surges, and bad harmonics from adversely affecting the performance of the
            device.
         A UPS traditionally can perform the following functions: 
        
            - Absorb relatively small power surges.
 
            - Smooth out noisy power sources.
 
            - Continue to provide power to equipment during line sags.
 
            - Provide power for a period of time after a blackout has
                occurred.
 
        
        In addition, some UPS devices or UPS-plus-software combinations
            provide the following functions: 
        
            - Automatically shut down equipment during long power
                outages.
 
            - Monitor and log power supply status.
 
            - Display the voltage (current draw) of the equipment.
 
            - Restart equipment after a long power outage.
 
            - Display the voltage currently on the line.
 
            - Provide alarms on certain error conditions.
 
            - Provide short-circuit protection.