Electrical safety systems

Offshore oil equipment data and boundaries for 84. safety systems, process systems, electrical systems, utility systems, cranes and drilling equipment. 

Explosives may be detonated electrically or nonelectrically. A nonelectric firing system will consist of a blasting cap, a length of time (safety) fuse or a firing device attached to the cap, and a means of activating the system match, fuse lighter, delay mechanism, or trip wire. The electric system requires an electric cap which has two wires attached, perhaps additional wire, and a battery or batteries to provide the current which activates the cap. 

IEC (1998), IEC 61508, Functional Safety of Electrical/Electronic/Programmable Electronic Safety-related Systems, Parts 1-7, Geneva International Electrotechnical Commission. 

The distributed control system (DCS) hardware areas are often referred to as "process computer rooms." I/O Rooms contain the incoming and outgoing wiring, cables and data highway links, and often small transformers and other related electrical equipment. Often, additional space is needed for a master process engineering computer terminal/work station for process control system changes and for critical safety instrumented systems (SIS) for interlocks and emergency shutdowns. 

Draft Standard IEC 61508, "Functional Safety of Electrical/ Electronic/ Programmable Electronic Safety-Related Systems", (Contact BSI/IEC for availability)... 

For arc furnace worker safety, high power electrical systems require proper design and precautions, and handling of molten materials requires a minimum of fire-retardant clothing and often dust masks. Water must be prevented from coming in contact with the melt. Furthermore, since open-arc furnace noise levels commonly exceed 100 dB A, hearing protection is a necessity. Noise is normally not a problem with smelting furnaces. 

Unfortunately, the gap has not been spanned by these approaches. As far as I know, only JRC Ispra has once financed a project of EWICS TC7 (European Workshop on Industrial Computer Systems, TC7, Safety, Reliability and Security, an expert group in this area), on Study of the Applicability of ISO/IEC 17799 and the German Baseline Protection Manual to the needs of safety critical systems (March 2003)(www.ewics.org) (3), where the gaps between the security standards and the safety-related system evaluation requirements have been analyzed for several sectors (medical, railways, nuclear, electric power networks) and in general. 

On account of their proximity to electrical systems and the accompanying potential heat and spark sources, wires and cables utilized in enclosed spaces are usually required to have fire safety characteristics as described in various codes and standards. 

First, safety critical systems must be reliable. These systems control releases in the event of accidents. It s necessary to have a critical analyzer, instrument and electrical system test program. This should consist of preventive maintenance and alarm and trip device testing for panel alarms, emergency isolation valves and other critical components. [7]... 

Application of Safety Instrumented Systems for the Process Industries, ISA-S84.01, Instrument Society of America, ISBN 1-55617-590-6, Research Triangle Park, NC, 1996. The objective of this document is to define the requirements for Safety Instrumented Systems (SIS) for the process industries. The SIS addressed here includes electrical, electronic, and programmable electronic technology. 

This part will discuss opportunities, primarily in the design of equipment, to make a plant inherently safer. This equipment includes mechanical equipment, piping systems, control systems, and electrical systems. There have been many developments in recent years that process designers can use to improve plant safety and make the plant inherently safer. 

Instruments, controls, and electrical system Safety and inspection... 

In the case of a BMS for an electric vehicle, the tasks of the safety-management system are ... 

The development of vehicle electrical systems operating at a nominal 42 V and its standardization with ISO is underway. A working group of the European Vehicle Electric System Architecture Forum has prepared a draft standard for this new voltage level [58]. The 42-V level was chosen as a compromise between the demand for an increased voltage to achieve higher efficiency in electrical and electronic components and the exclusion of safety hazards, even under extreme operational conditions like load dump, etc. The term 42-V PowerNet , or simply PowerNet , is now established worldwide [9,11,59]. 

Electrical Distribution Systems. Starting at the source of power supply, the basic electrical system includes transmission, substation, transformation, switching, distribution by feeders, the items of use, and protective safety equipment. Electrical flow sheets are prepared, using... 

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