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Intrinsically safe

Displacer units are tolerant of specific gravity shifts within their range, require no power to operate, are intrinsically safe, and can be easily field cahbrated. A single displacer unit can control up to three alarm set points or up to three pumps with different spans. They can be caHbrated for set points or pump spans from 0.15—30 m from the top of the vessel mounting. [Pg.208]

ISA RP 12.6. 1987. Installation of Intrinsically Safe Systems for Hazardous (Classified) Locations. (ANSI approved.) Instrument Society of America, Research Triangle Park, N.C. [Pg.150]

Intrinsically Safe Equipment and wiring which is incapable of releasing sufficient electrical or thermal energy under normal or abnormal conditions to cause ignition of a specific hazardous atmospheric mixture or hazardous layer. [Pg.163]

To contain the temperature of the electrical circuits within safe limits for a particular temperature class of the surroundings, the maximum current rating for a minimum size of a conductor is also stipulated in ICC 60079-1 I. The constructional requirements also stipulate the minimum clearances and creepage distances in air between the conducting parts of all the intrinsically safe L lectrical eirctiits. [Pg.183]

Specifications for intrinsically safe electrical system i General recommendations on the selection of the appropriate group of electrical apparatus based on safe gaps and minimum igniting currents 3682/1991 BS 5501-7/1977 BS 5501-9/1982 BS 5345-1/1989 ... [Pg.192]

Textile motors Crane motors Determining the size of motor Sugar centrifuge motors Motors for deep-well pumps Motors for agricultural application Surface-cooled motors Torque motors or actuator motors Vibration and noise level Service factors Motors for hazardous locations Specification of motors for Zone 0 locations Specification of motors for Zone I locations Motors for Zone 2 locations Motors for mines, collieries and quarries Intrinsically safe circuits, type Ex. f Testing and certifying authorities Additional requirements for ciritical installations Motors for thermal power station auxiliaries Selection of a special-purpose motor... [Pg.996]

Must be air purged, explosion proof, or intrinsically safe to be used in hazardous areas. [Pg.293]

Intrinsic Safety. Static electrical concepts such as minimum ignition energy do not directly apply when assessing the safety of electrical circuits such as radios, flashlights and instmmentation. Intrinsically safe electrical equipment is usually available which has been subjected to fault analysis and testing. The equipment must be certified for the flammable atmosphere in which it will be used (NFPA 497). Refer to texts on Intrinsic Safety such as [63]. [Pg.5]

Of the instmments described only some are suitable for use outside the laboratory. Where any instrument is carried into a flammable environment it should either be certified as intrinsically safe for exposure to the flammable atmosphere or isolated from the atmosphere such as by keeping it within a purged enclosure. Any probe connected to the instmment must be separately considered as a possible ignition source. Electrometers are described in [ 1531. A more general review of electrostatic instruments is given in [ 136]. [Pg.50]

Hannerz, H., 1983, Towards Intrinsically Safe Light Water Reactors, ORAU/IEA-83-2(M)-Rev. Institute for Energy Analysis. [Pg.480]

Intrinsically safe Instruments that can be safely operated in an explosive or corrosive atmosphere. [Pg.1452]

The design of intrinsically safe equipment is governed by the rules of NFPA Publication No. 493, Standard for Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, II, and III, Division 1, Hazardous Locations. It is cautioned, however, that the design of intrinsical-... [Pg.523]

The mere fact that voltage, current, or even both, are at low levels does not guarantee a circuit to be intrinsically safe, even though intrinsically safe circuits do utilize relatively low voltage and current levels. Intrinsically safe systems employ electrical barriers to assure that the system remains intrinsically safe. The barriers limit the voltage and current combinations so as not to present an ignition hazard should a malfunction develop. Typically, devices upstream of barriers are not intrinsically safe and are installed in control rooms or other unclassified locations. All devices and wiring on the downstream side of the barriers are intrinsically safe and can be installed in classified areas. [Pg.524]

An additional benefit of intrinsically safe systems is the reduction of electrical shock hazards. It is cautioned, however, that intrinsically safe systems are not necessarily tested specifically for personnel shock hazards. [Pg.524]

Circuit capacitance and inductance, including the values of these parameters for interconnecting wiring, are integral parts of the overall analysis. It is not always possible to assure that the system will be maintained as designed with only approved intrinsically safe components and with circuits of the capacitance and inductance as originally installed. For this reason, intrinsically safe systems are used primarily at locations where there are sufficiently trained personnel to assure that the intrinsic safety of the system is always maintained. [Pg.524]

C22.2, No. 157 Intrinsically Safe and Nonincendive Equipment for Use in Hazardous Locations... [Pg.548]

RP12.6 Installation of Intrinsically Safe Instrument Systems for Hazardous (Classified) Locations... [Pg.550]

Standard for Intrinsically Safe Apparatus and Associated Apparatus for Use in Class I, IE and III, Division 1 Hazardous Locations... [Pg.551]

The use of intrinsically safe electrical and instrumentation equipment in appropriately designed environments can guard against many electrically related discharges. Reference should be made to authoritative books on this subject. [Pg.536]

Optical fiber cables and fiber optic devices approved as an intrinsically safe system suitable for the hazardous (classified) location involved shall be installed in accordance with Sections 504-20 and 770-52. [Pg.637]

Intrinsically Safe Systems. Intrinsically safe apparatus and wiring shall be permitted in any hazardous (classified) location for which it is approved, and the same provisions of Articles 501 through 503, 505, and 510 through 516 shall not be considered applicable to such installations, except as required by Article 504. [Pg.637]

Installation of intrinsically safe apparatus and wiring shall be in accordance with the requirements of Article 504. [Pg.637]

See other pages where Intrinsically safe is mentioned: [Pg.208]    [Pg.211]    [Pg.97]    [Pg.397]    [Pg.504]    [Pg.786]    [Pg.786]    [Pg.786]    [Pg.114]    [Pg.116]    [Pg.165]    [Pg.179]    [Pg.180]    [Pg.182]    [Pg.182]    [Pg.182]    [Pg.270]    [Pg.293]    [Pg.400]    [Pg.419]    [Pg.523]    [Pg.523]    [Pg.524]    [Pg.549]    [Pg.485]   
See also in sourсe #XX -- [ Pg.148 ]

See also in sourсe #XX -- [ Pg.146 ]



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