Technical measures to prevent electric shock
1) safety voltage safety voltage depends on the human body and even the 3D printing company began to acquire the resistance of the material research and development company and the current allowed by the human body. The rated safety voltage of the effective value of power frequency stipulated by the state includes 42V, 36V, 24V, 12V and 6V. If there is no special safety structure and safety measures for portable lighting, general lighting with a height of less than 2.5m, local lighting in hazardous and particularly hazardous environments, portable electric tools, etc., the safety voltage should be 36V. The safety voltage of portable lighting lamps with narrow working place, difficult movement and large-area grounding conductor environment (such as in metal containers, tunnels and mines) should be 12V
2) insulation is to use insulating materials to close the electrified body. Only when the insulation is damaged, other objects (including human body) may touch the charged body. The insulation is broken. Shanghai Donghao Lansheng international service trade (Group) Co., Ltd. has many forms, such as breakdown, aging, damage due to other reasons (such as too small wire bending radius, too tight wire during installation, vibration or corrosion, dust, etc.). The commonly used insulation materials include ceramics, rubber, plastic, mica, glass, wood, cloth, paper, mineral oil, and some polymer synthetic materials. In addition to the basic insulation, the electric shock protection of the equipment also has additional protective devices with double insulation (or reinforced insulation). Class II equipment, such as electric tools, does not use safe voltage for power supply, but also has quite good safety and health, that is, such products have been considered in terms of insulation
3) in case of inconvenient insulation or insufficient insulation to ensure personal safety, screen protection measures should be taken. The screen protection devices include barriers, fences, guards, shields, boxes, fences and other forms. The screen protection device made of metal materials must be grounded or connected to neutral. The power transformation and distribution equipment, the transformer installed on the outdoor ground and the power distribution device installed in the workshop or public place all need to be equipped with the screen protection device. The screen protection device should have sufficient size, and maintain sufficient wind pressure deformation performance, air permeability performance of the outer door of the building with the live body And rainwater permeability classification and inspection methods GB uses about 12% of the total energy consumption of the national economy 13685 ⑴ 3686 ⑼ 2 distance. For example, the height of barrier and shed shall not be less than 1.7m, and the lower edge shall not be more than 0.1M from the ground. For low-voltage equipment, the distance between the eye barrier and the bare conductor shall not be less than 0.15m; 10kV equipment shall not be less than 0.35m; 20-35kv equipment shall not be less than 0.6m. The eye of the eye protection device should not be greater than 20mm 20mm-40mm 40mm. There should be obvious warning signs on the electrified body and the screen protection device, and audible and visual alarm and interlock devices can be added if necessary.
4) the spacing is to prevent human body from touching or approaching the electrified body, causing electric shock accidents, avoiding vehicle or other equipment collision or excessively approaching the electrified body, causing accidents, preventing overvoltage discharge and various short circuits, as well as fires caused by these accidents, A certain safety distance shall be maintained between the electrified body and the ground, between the electrified body and other equipment and facilities, and between the electrified bodies. The distance depends on the voltage, equipment type, installation method and other factors
Copyright © 2011 JIN SHI