GOST 50571.3-94 Electrical installations of buildings. Part 4. Security requirements. Protection against electric shock

GOST 50571.3-94 (IEC 364-4-41-92) UDC 696.6:006.354 Group E08 STATE STANDARD OF THE RUSSIAN FEDERATION Electrical installations of buildings Part 4 Protection for safety. PROTECTION FROM ELECTRIC SHOCK Electrical installations of buildings. Part 4. Protection for safety. Protection against electric shock OKS 3402 Effective date 1/1/1995 Preface 1 prepared and submitted to the Technical Committee for Standardization TC 337 Electrical equipment of residential and public buildings 2 adopted and put into operation the Decree of the State Standard of Russia 31.10.1994, № 254 3 This standard contains the full authentic text of the international standard IEC 364-4-41-89 (1992) "Electrical installations rear. Part 4. Security requirements. Chapter 41. Protection against electric shock 4 Enter FEATURE 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." Requirements of the standard should be considered in all areas falling within the scope of the standardization and certification of electrical installations of buildings: the development and revision of standards, rules and regulations on the device, testing and commissioning of electrical installations. To ensure identification requirements established in this standard and the requirements of international standard IEC 364-4-41 (1992) and for the convenience of a standard for reference to it in other regulatory documents, interconnected with a set of international standards of IEC 364 for electrical building, in the present Standard retain the numbering of sections and paragraphs, adopted in IEC 364-4-41 (1992). The standard uses the term "system BSNN" (English equivalent: "SELV system") instead of the full name of the term "low voltage system is safe." The term "system ZSNN" ("PELV system") used in the case of a grounded circuit system BSNN ("SELV system"). Similar to the previous terms, the term "system of functional extra-low voltage is presented in abbreviated form" system FSNN "(" FELV system "). BSNN system - a protective measure, which provides as follows. The primary protection is carried out by limiting the voltage in the circuit system BSNN to ultralow values; branch circuit system BSNN from all other circuits. Additional protection is that the separation of chains of BSNN from other circuits is protective division, a chain of BSNN separated from the land. Intentional connection exposed conductive parts to the protective conductor is not allowed. ZSNN system - a protective measure, which provides as follows. The primary protection is carried out by limiting the voltage in a grounded circuit system ZSNN to ultralow values ??separated by a chain of ZSNN from all other circuits. Additional protection is that division of the circuit from other circuits is protective division. Allowed connection exposed conductive parts of electrical equipment (except electrical grade III) to the protective earth conductor or, if required by the relevant standard for the product. FSNN system - a protective measure, used in cases where the operating conditions (operation) is used to supply electrical power, not exceeding - 50 VAC (rms) or 120 V DC (rectified) current, and there is no need or possibility of application systems BSNN and ZSNN, and consisting of the following. Protection against direct contact (hereinafter - direct contact) is performed by fencing or shells, using reinforced insulation (if required). Protection against indirect contact by connecting exposed conductive parts of equipment in the circuit protective conductor FSNN with the primary circuit, provided that the primary circuit is protected with an automatic power-down, a compound of exposed conductive parts of equipment in the chain FSNN with an ungrounded system bonding of the primary circuit, for which protection by electrical separation. Requirements for protective measures against electric shock regulated 12.1.019-79 GOST, GOST 12.1.030-81, GOST 12.1.038-82, "Rules of Electrical Code" (SEP). The above documents are inferior to international standards IEC 364-3 (1993) and IEC 364-4-41 (1992) for systematic technical standards and requirements for the comprehensiveness of factors impact the environment and operating conditions. Existing RB regulates the requirements for electrical safety, according to which should carry electrical grounding or neutral: 1) at a voltage of 380 V and above AC 440 V and above, DC - in all electrical systems, 2) at rated voltages above 42 but below 380 VAC and above 110 but below 440 V dc - only in rooms with high-risk, high-risk and in outdoor settings. Not required to perform electrical grounding, or neutral at rated voltages to 42 V AC to 110 V DC in all cases, except for hazardous areas and electric installations. PUE requirements do not provide electrical safety both indoors and in areas of outdoor installations. To ensure electrical safety according to IEC 364-4-41 (1992) is required to perform electrical grounding, or neutral: 1) at nominal voltage 50 V AC (rms), and more than 120 V DC (rectified current) - in all electrical systems, 2) at rated voltages above 25 V AC (rms) or above 60 V DC (rectified current) - only in rooms with high-risk, high-risk and in outdoor installations. Not required to perform electrical grounding, or neutral at rated voltages of 25 VAC or 60 VDC in all cases, except for hazardous areas and electric installations. Protection against direct contact by fencing or shells or isolation is not required if the electrical equipment is within range of bonding and a rated voltage not exceeding: - 25 VAC or 60 VDC, provided that the equipment is normally operated only in dry areas and low probability of human contact with the parts, able to be energized - 6 VAC or 15 VDC (rectified) current in all other cases. Comparison of matched standards EMP and IEC standards suggests the need for more stringent requirements for protective measures in the design, construction, installation and operation of electrical equipment of buildings. Application of the requirements of IEC 364-4-41 (1992) will enhance the reliability and electrical safety of electrical installations of buildings. 1 Scope This Standard specifies requirements to ensure protection against electric shock during operation of electrical equipment of buildings. Scope of Standard - GOST R 50571.1. The requirements of this standard are mandatory. LEGAL LINKS This standard references to the following standards: GOST 12.1.019-79 SSBT. Electrical safety. General requirements and range of protection GOST 12.1.030-81 SSBT. Electrical safety. Protective earthing and neutral GOST 12.1.038-82 SSBT. Electrical safety. Maximum permissible touch voltages and currents GOST 50571.1-93 Electrical installations of buildings. Key provisions of 41 PROTECTION AGAINST ELECTRIC SHOCK 410 General Protection against electric shock should enforce the measures set out in sections: - 411 for protection from direct and indirect contact; - 412 to protect against direct contact; - 413 for protection against indirect contact . 411 Protection from direct and indirect contact through 411.1 Protection Systems BSNN and ZSNN 411.1.1. Protection against electric shock feel secured when: - rated voltage not exceeding 50 V AC (rms) or 120 V DC (rectified current) - Power supply is one of the sources specified in 411.1.2 - all conditions 411.1.3 and 411.1.4 for ungrounded circuits of BSNN or 411.1.5 for the grounding circuits of the system ZSNN. Note - If the circuit is powered from the network through a high voltage equipment such as auto, potentiometers, semiconductor devices, etc., it is considered part of the primary circuit, and it must be protected by security measures employed in the primary circuit. 411.1.2