Uninterruptible power sources

I-3.6.3 Uninterruptible power sources or redundant backup systems shall be considered to help prevent overpressure/unintentional shutoff situations caused by power outages. 

Voltage Notch Due to Uninterruptible Power Source Unit... 

Static uninterruptible power sources (UPSs) have no rotating parts, such as motors or generators. These are devices that maintain power to the loads during loss of... 

FIGURE 2.14 Offline uninterruptible power source (UPS) system. 

FIGURE 2.16 Output voltage waveform from an offline uninterruptible power source (UPS) system. The ringing during switching is evident during the first cycle. 

FIGURE 2.18 Rotary uninterruptible power source (RUPS) system using a diesel engine, AC motor, and AC generator to supply uninterrupted power to critical loads. 

UPS (uninterruptible power source) URC (uniform resource characteristic) URI (uniform resource identifier)... 

Lead-acid vehicles (SLI and traction), aircrats, submarines, forklifts, uninterruptible power sources, telephone exchange stations. 

Uninterruptible Power Sources, Stationary Energy Storage... 

It is standard practice to have the DCS and safety systems powered by an uninterruptible power source (UPS). Whenever the normal power supply fails, the UPS will immediately switch to its batteries, which can keep the systems powered until backup power can be applied or the process shut down. The UPS should be able to operate the control systems for at least 20 min. 

The Instrument and Control Power Supply provides 120 Vac single phase power to instrument and control loads that do not require an uninterruptible power source. 

The Technical Specifications will include specific requirements regarding plant operational restrictions as they apply to the 120 VAC vital instrument bus and inverters. Operational restrictions are provided in the Technical Specifications to assure the Onsite Power System availability and thus an uninterruptable power source for safety-related systems and components. Incorporated in these restrictions is a periodic evaluation of the Onsite Power System bus condition which considers such availability items as proper breaker and bus alignment, and adequate bus voltage. 

Sukumara, G.V., Parthasarathy, A., and Shankar, V.R, Fuel Cell Based Uninterrupted Power Sources , Power Electronics and Drive Systems, Proceedings Volume 2, pp. 728 -733, 1997. 

Two of the rechargeable batteries, namely the Pb-add and Ni-Cd, have impressively long histories. The Pb-acid batteries were first manufactured as early as 1860, whereas the Ni-Cd batteries were first manufactured around 1910. The other rechargeable batteries such as zinc-manganese dioxide (Zn-MnOj), Ni-MH, and Li are relatively young, but they are widely deployed in portable devices and sensors. The Li and Ni-MH batteries are best suited for portable electronic components, where rehability, longevity, and uninterrupted power sources are the principal requirements. Table 1.4 describes the performance capabihties and important characteristics of rechargeable batteries widely used to power portable electronic devices and sensors. 

Industrial Applications. Larger-sized batteries, usually rechargeable, are used in these applications. In many of these applications, the batteries are used as back-up power in the event of an AC power failure. In some instances, such as with munitions, navigation aids and satellites, primary or reserve type batteries are used where an electrical source is not available for recharging. This is another area that is expanding rapidly to meet the demands for uninterrupted power sources (UPS) for computer and other sophisticated systems which require 24/7 operation with extremely high reliability. 

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