Back-up devices

The electric double-layer capacitance is almost linear to the accessible surface area of the electrolyte ions. Additionally, the chemically/electrochemically stability, electric conductivity, and adequate commercial price are necessary for the EDLC electrode, so the activated carbons are suitable as practical electrode materials. The EDLC has been commercialized as a memory back-up device since the 1970s because of its high cycle efficiency and its long cycle life. Recently, the EDLC is also being considered to be one of the promising systems for... 

Access to all sites of the OPCW and key components of the IMS, such as the servers and mass storage devices, must be controlled. All hardware in the confidential part of the IMS and especially workstations, servers and user terminals shall be protected, not only from theft or criminal damage, but also from unauthorised physical access and tampering attempts. In addition, maintenance and repair activities on IMS hardware shall be supervised and recorded. Access to such hardware items as servers, printers, back-up devices, as well as other output devices, shall be limited to staff members with appropriate clearances. 

Failure of compo- Ensure all system components, including flexible nents in connectors are rated for maximum feasible subatmospheric vacuum conditions pressure convey-, Ensure adequate pressure control system and ing operations. back-up (e.g., vacuum relief devices) API 2000 CCPS G-3 CCPS G-11 CCPS G-22 CCPS G-29 CCPS G-3 9... 

The bus system of a switchgear assembly, its interconnecting links and wires are the protected type components, whereas an interrupter (breaker, switch or a fuse) may be a protecting or protected type, depending upon their application and location in the circuit. A contactor and an OCR are therefore protected devices in the same context, for they provide no short-time protection. A protecting device may become protected when it is also provided with a back-up protection. 

The number of flare headers and individual subheaders connected to them depends upon the type of vapors handled, process temperature conditions, and the available back-up pressure or limitations of the pressure receiving devices specified for the system. This section reviews some of the important design criteria and considerations for the headers and subheaders, which is an integral part of the overall flare system design. 

This approach has been performed on. several offshore production facilities with inconsistent results. That is, items that were identified by one set of evaluators as required for protection in one design were not required by another set of evaluators in a completely similar design. In addition, potential failure of some safety devices on one facility caused evaluators to require additional safety devices as back-up, while the same group in evaluating a similar installation that did not have the initial safety devices at all did not identify the absence of the primary safety device as a hazard or require back-up safety devices. 

The primary protection for high temperature, which could lower the maximum allowable working pressure below the PSV setting, is a high-temperature sensor (TSH), which shuts in the inlet or the source of heat. Back-up protection is provided by leak detection devices. 

System hardware maintenance also presents some challenges. Trial personnel at the Central location first attempt resolution of hardware malfunctions. If they are unable to resolve the problem, personnel at the central location try to resolve the problem, and if that does not solve the problem a repair order is requested from the vendor as long as there is an active warranty. If the problem persists, the participating site is instructed to ship the device to the central location. If the device is the computer, the site coordinator (SC) is instructed to back up the database before shipping the computer. Personnel... 

Rupture Disc and Spring Loaded Relief. Normal Relief May Co Through Spring Loaded Device/ and Rupture Disc Is Back-up for Larger Reliefs. 

In the first step the chlorine from the tail gas and chlorine feed reacts with the caustic in the jet-loop reactor. The advantage of the jet-loop reactor is that it also acts as a suction device for the gas stream. The residence time of the liquid in step one is dependent on the capacity of the hypochlorite production and liquid level in the tank and varies between 1 and 4 h. A heat exchanger in the loop controls the temperatures in steps one and two. The amount of caustic in the feed-tank of step two is the back-up for failure of chlorine liquefaction. 

Portable fuel-cell systems are systems that produce electricity for devices with a performance ranging from several watts to 10 kilowatts. The heat produced in the process is a by-product that is normally not used. The system has, therefore, to be cooled down by fans or cooling surfaces, etc. A wide range of applications is possible for fuel cells from small electronic devices like camcorders, mobile phones, laptops, etc. to electric tools, back-up systems, or power generation on boats or caravans. 

Fuel cells have also been used for Skylab, a space station launched on May 14, 1973, and in orbit for more than six years, as well as in the space shuttles. Other uses for these reliable devices include providing electricity at remote facilities that are beyond the reach of power lines, and as back-up generators at hospitals, which cannot afford to lose power for any length of time. 

When the element is read out a solid-state device called a multiplexer attaches the detector to a voltage source which charges the capacitor back up to a standard potential. 

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