GOST 50571.4-94 (IEC 364-4-42-80) UDC 696.6:006.354 Group E08 STATE STANDARD OF THE RUSSIAN FEDERATION Electrical installations of buildings Part 4: Protection for safety. PROTECTION AGAINST THERMAL EFFECTS Electrical installations of buildings. Part 4. Protection for safety. Protection against thermal effects OKS 3402 Effective date 1/7/1995 Preface 1 prepared and submitted to the Technical Committee for Standardization TC 337 "Electrical residential and public buildings" 2 approved and put into effect by Decision of State Standard of Russia from 06.12.94 № 299 3 This standard contains full authentic text of the international standard IEC 364-4-42 (1980) "Electrical installations of buildings. Part 4. Security requirements. Chapter 42. Protection against thermal effects "with additional requirements which reflect the needs of the economy four first introduced INTRODUCTION This standard is part of the state standards for electrical installations of buildings developed on the basis of the standards of the International Electrotechnical Commission IEC 364" Electrical installations of buildings ". On the content of established standards and requirements of this standard is a fundamental part of the requirements for protecting people, equipment and environment from the thermal effects that occur during the operation of electrical installations of buildings, whose provisions shall apply in all areas falling within the scope of the standardization and certification of electrical installations of buildings when developing and revising standards, rules and regulations on the device, testing and commissioning of electrical installations of buildings. The standard does not regulate the fire safety of buildings and technological equipment. Numbering sections and paragraphs of this standard are in conformity with IEC 364 standards for electrical installations of buildings. The numbering system established in the standards IEC 364, provides an indication of numbers of parts and chapters of the international standard IEC designation numbers of sections and paragraphs of private standards. For example, in the notation of paragraph 422.3 of the standard figure 4 represents the part number, 42 - chapter number 422 - the section number of the international standard IEC 364-4-42 (1980). The use of this numbering system provides vzaimouvyazku requirements of private standards set standards for electrical installations of buildings according to the rules adopted by the IEC Technical Committee 64 "Electrical installations of buildings". The requirements of this standard are consistent with the requirements of the current "Rules of Electric" (SEP, the sixth edition), and approved Glavtehupravleniem Gosenergonadzor USSR Ministry of Energy. Additional requirements that reflect the needs of the economy, the text of this Standard are in italics. 1 Scope This standard establishes general requirements for the protection of people, equipment and environment from the thermal effects that occur during the operation of electrical installations of buildings. Scope of Standard - GOST R 50571.1. When placing electrical fire in the areas of standard should be applied in conjunction with the Regulations for Electrical Installation "(Chapter 7.4), and approved Glavtehupravleniem Gosenergonadzor USSR Ministry of Energy. 2 Normative references in this standard references to the following standards: GOST 12.1.004-91 SSBT Fire Safety. General requirements of GOST R 50571.1-93 Electrical installations of buildings. Key provisions of 4 Protection against heat 421 General People, stationary equipment and materials which are near electrical installations must be protected from the dangerous thermal effects, including thermal radiation associated with the operation of electrical equipment, in particular for the following effects caused by thermal effects: ? burning or destruction of materials; ? of burns; ? threat to safe operation of electrical equipment; ? fire. 422 Fire protection 422.1 Electrical installations of buildings and their constituent electrical equipment (hereinafter - the electrical equipment) should not pose a fire hazard for the nearby other equipment and materials. Fire safety of electrical installations of buildings should be provided in accordance with the requirements of GOST 12.1.004. Electrical equipment, part of the electrical installations, must meet the requirements set forth in the relevant state standards. 422.2 If the outside temperature can reach values ??of electrical equipment, causing a fire located on or near the materials, electrical equipment should be: ? or installed on a pedestal (gasket) of materials that can withstand a temperature and having low thermal conductivity; ? or enter it in the shell of materials with low thermal conductivity; ? or separated from the structural elements of buildings materials with low thermal conductivity and can withstand a temperature; ? or set at a sufficient distance from any material to which that temperature can have a destructive thermal effect, providing reliable heat dissipation and using the reference construction with low thermal conductivity. 422.3 If the stationary equipment and materials may be exposed to sparks or arcing at electrical work, such electrical equipment should be: ? or fully protect the materials resistant to the formation of an electric arc; ? fencing or special screens Arc resistance from elements of buildings, for which electrical arc can have a devastating effect; ? or set at a sufficient distance from the structural elements of buildings to which the electric arc could have a harmful effect, providing a reliable arc quenching. Materials resistant to the effects of an electric arc to be used as protective equipment, must be fireproof, have low thermal conductivity and sufficient thickness to provide mechanical stability. 422.4 Stationary electrical exhibits the effect of focusing or concentration of heat must be removed from any stationary object or element of design of buildings so that the object or elements under normal conditions are not exposed to dangerous temperatures. 422.5 If the electrical equipment in each unit contains a significant amount of flammable liquid shall be provided for such precautions, in which flammable liquids or products of combustion (flame, smoke and toxic gases) do not spread to other parts of the building. Notes 1 As a precautionary measures may include the following: ? device approved oil wells, which is going to flammable liquid and which ensure its extinction in the event of a fire; ? installation of electrical equipment in the rooms (chambers) with fire-resistant walls, thresholds, or using other measures to prevent the spread of burning liquid on to other parts of the building, with rooms (chambers) should be equipped with individual ventilation with the release of the building. 2 Number of flammable liquid, equal to 25 liters considered significant. 3 When the amount of flammable liquid at least 25 liters is enough to ensure its nerastekanie. 4 We recommend turning off electrical equipment in case of fire. 422.6 Materials fencing installed around the electrical equipment at its installation, must withstand the maximum temperature that can occur when operating electrical equipment. Flammable materials should not be used for devices such fences, unless steps are taken to warn their fire, such covering fireproof or nonflammable materials with low thermal conductivity. 423 PROTECTION FROM BURNS Available to touch electrical parts should not reach temperatures capable of causing burns, and their values ??must not exceed specified in Table 42A. All parts of electrical installations, which can reach during normal operation of electrical equipment, even for a short period of time, temperatures exceeding the values ??shown in Table 42A, shall be protected to prevent accidental contact with them. The temperatures shown in Table 42A shall not apply to electrical equipment, if the standards for this equipment is installed, from the standpoint of protection from burns, other maximum values. Table 42A Maximum temperatures are available for touching parts of electrical equipment under normal operating conditions available for a touch of the electrical material accessible parts Maximum temperature, ° C Knobs Metal 55 is 65 parts of metal, not intended for metal in 1970 holding hands, not the metal of 80 parts, not intended for Metal contact 80 under normal conditions of service no metal 90424 Overheat 424.1 Inlet heating systems 424.1.1 Inlet heating systems, except for accumulation of heating boilers shall be such that their heating elements could not be included until a set point of air flow and would shut down the termination of air supply. Incoming air heating systems should be equipped with two mutually independent temperature limiter, excluding any allowable temperature in air ducts. 424.1.2 Frame and sheath heating elements must be made of fireproof material. 424.2 Equipment for producing hot water or steam All the devices for hot water or steam must be protected from overheating under all operating conditions by means of constructive remedies or methods of installation. If for any reason, these devices do not satisfy the requirements of relevant standards, protection should be provided through the automatic shut-off without the self-return, triggered by the thermal relay. If the device has no free outlet to drain water, it must be equipped with water pressure limits. _________________ Key words: electrical buildings security, protection from thermal effects, protection against fire, protection from burns Posted 06/26/2008 GOST on "Electrical, lighting, security systems," GOST 15597-82 Fixtures for industrial buildings. General specifications GOST 2.702-75 Unified system for design documentation. Rules for making electronic circuits with GOST 2.752-71 Unified system for design documentation. Graphical symbols in diagrams. Robot device GOST 2.755-87 Unified system for design documentation. Graphical symbols in electrical circuits. Device switching and contact connections GOST 2.756-76 * Unified system for design documentation. Graphical symbols in diagrams. Is often perceived electromechanical devices GOST 2.757-81 * Unified system for design documentation. Graphical symbols in diagrams. Elements of the switching field for switching systems GOST 2.758-81 Unified system for design documentation. Graphical symbols in diagrams. Signal Technology GOST 2.762-85 * Unified system for design documentation. Graphical symbols in electrical circuits. Frequencies and frequency bands for transmission systems GOST 2.763-85 * Unified system for design documentation. Graphical symbols in electrical circuits. Device with a pulse-code modulation GOST 2.764-86 Unified system for design documentation. Graphical symbols in electrical circuits. Integrated optoelectronic display elements GOST 2.768-90 Unified system for design documentation. Graphical symbols in diagrams.
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