Power outage

Reliable during power outage for short period of time, dependent on size of air surge vessel. 

Means to initiate alanii signals in tlie event of a power outage... 

Generally, electricity is purchased from a local supplier. Power is required to generate motor drives for lighting and for general uses. Note tliat, in tlie typical distillation operation illustrated in Fig. 16.3.3, a power outage for the entire system would cause a less severe effect tlian failure of a reflux pump alone. 

Hazard, risk, failure, and reliability are interrelated concepts concerned witli uncertain events and tlierefore amenable to quantitative measurement via probability. "Hazard" is defined as a potentially dangerous event. For example, tlie release of toxic fumes, a power outage, or pump failure. Actualization of the potential danger represented by a hazard results in undesirable consequences associated with risk. 

Figure 20.8.1 shows the event tree with tlie initiating event and the external power outage, denoted by I. Labels for die oUier events on the event... 

Sometimes, even in this electronic age , paper is still the medium of choice. For retained records that must be made available to personnel responding to an emergency, paper is a better medium than electronic media, because paper can remain accessible during emergency events (e.g., power outages, fires, floods, etc.) that could render electronic records inaccessible. 

If we use a controller with positive gain (+KC), the controller output increases as the liquid level drops. We can only reduce the flow if we use an air-to-close valve (-Kv). In the case of a power outage, the valve will stay open. This fail-open valve can drain the entire tank, an event that we may not want to happen. 

To minimize damage due to power outage, the Celanese Corporation in their plant at Newark, N.J., instituted a policy of always generating half its own power. Merck Company installed additional auxiliary steam power to insure constant refrigeration for its biochemicals at its West Point, Pa., plant. At Allied Chemical s phenol plant in Frankfort, Pa., electric devices on air compressors and pumps were replaced by steam-operated controls, and diesel generators were installed to maintain cooling water circulation. 19... 

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. 

GM and Hydrogenics have developed a fuel cell unit that provides back-up power to cell phone towers during power outages. Hydrogenics will market the fuel cell unit with Nextel. 

As companies scrambled to find new ways to lower the once fixed cost of their energy use, these newer options also allowed companies to protect themselves against unexpected power outages. 

At such high throughputs and large product hold-ups, these plants are required to be very robust [2], More than one year of continuous production without maintenance is expected. In addition, the process needs to be able to be restarted after power outages of some hours without the loss of further production and with minimal off-spec material. 

The reliability of the power supply should be determined, taking into account the frequency of power outages and extent of interruption. Consideration should be given to connecting electrically driven fire water pumps to the emergency power system, where one exists. 

Electronic Overwritten RAM lost in power outage Destroyed Data averaged and individual samples overwritten Incomplete... 

There was a power outage shordy before the incident. 

On August 1, 2001 at 10 30 A.M., a control room operator remotely started the feeds to Kettle No. 3 in the catalyst preparation area. The normal procedure was to fill the kettle to approximately 80%, but Kettle No. 3 was apparently completely filled this time. The level indicator showed a high level, but the alarm did not sound. (The alarm was later found to be inhibited.) A high-pressure alarm for this vessel was acknowledged at 11 03 A.M. by the control room operator. At 11 00 A.M., a severe thunderstorm had started and within 5 minutes caused a power outage throughout the immediate vicinity. The ambient temperature was about 83°F and winds were from the northwest at about 3 mph. 

The commander of the plant fire brigade sent a team member to the fire pump house. The electric fire pump was inoperable due to the power outage. One diesel fire pump was known to be impaired due to mechanical problems and other diesel fire pump had failed to start because its batteries were dead. Several maintenance personnel were sent immediately to repair this diesel fire pump. 

Failure of the physical conditions in the aseptic processing area (e.g., power outage, failure of FIEPA units)... 

In addition to production metering and automatic well testing, meter site automation detects equipment malfunctions such as high fluid levels in separators and site power outage. 

If necessary repairs are not carried out on the transmission system considerable power outages will occur due to system failure. 

Superconductive wire and systems have seen renewed interest from utilities and government alike after the August 2003-U.S. power outage. Superconductors have the ability to effectively replace overworked portions of the electric grid that contributed to the outage. 

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