Learn to use electricity temporarily every dayoneSafety management requirements for lighting electricity on construction sites
General requirements for construction lighting
1) General lighting, local lighting or mixed lighting should be set up in places such as operation in potholes, night construction or operation workshops, yard roads, warehouses, offices, canteens, dormitories and places with poor natural lighting. In a workplace, there must be no local lighting.
2) After the power outage, the operator needs to evacuate the site in time for special projects, such as the project of working at height at night and the tunnel, deep pit, hole engineering and other places with poor natural lighting, and emergency lighting must also be installed by the independent self-provided power supply (generally refers to the self-provided generator set).
3) For the construction projects that affect the safe passage of pedestrians and vehicles at night, such as excavated trenches, grooves, holes, etc., eye-catching red warning lighting should be set up on their adjacent edges.
For tall mechanical equipment or facilities that may affect the safe passage of aircraft and other aircraft at night, such as tower cranes, external elevators, etc., eye-catching warning lighting should be set up at the top of it.
4) Set up security lighting that is not affected by power outages as needed. The power supply for security lighting is generally taken from its own generator set.
Illuminator selection
1) For general places with normal humidity (relative humidity 75%), ordinary open illuminators can be selected. For example, ordinary light bulbs, fluorescent lamps, iodine-tungsten lamps, high-pressure mercury lamps, sodium lamps and so on.
2) Wet or particularly humid (relative humidity "75%), which is a dangerous place for electric shock, must choose a closed waterproof illuminator or an open illuminator equipped with a waterproof lamp head.
3) Places that contain a large amount of dust but do not have a fire hazard belong to the general places with electric shock hazards, and dust-proof illuminators must be selected to prevent dust from affecting the safety of the illuminators.
4) Places with ** and fire hazards, such as places with a large number of combustible dust, combustible gases, combustible liquids, or combustible solids, are also dangerous places for electric shock. For these dangerous places, appropriate explosion-proof illuminators should be selected according to the level of hazardous places, as detailed in the current national standard "Design Code for Shenli Device in Fire Hazard Environment" (GB50058). Here is an example to illustrate, assuming that the fire hazard place belongs to the fire hazard area with solid combustible substances according to the above-mentioned national standards, and belongs to the environment that can cause disaster hazards in terms of quantity and configuration, according to the specification, the protective structure of the lighting fixtures should be IP2X level.
5) There is a place with strong vibration, such as the on-site lighting of large construction machinery such as shield machine in the road or large hole, because this construction site generally has a relatively strong vibration, so it is necessary to select anti-vibration illuminators according to the regulations.
6) There are strong corrosive media such as acid and alkali, because these strong corrosive media have a strong corrosive effect on the electrical structure and insulation structure of the lamp, it is easy to cause poor electrical contact or insulation damage, and even the lamp head is overheated or short-circuited and burned, so it is necessary to choose acid and alkali resistant illuminators.
3.Lighting power supply options
In general places, the lighting power supply voltage should be 220V, and the illuminator with a rated voltage of 220V can be selected.
Tunnels, civil air defense works, high temperatures, conductive dust, relatively humid or the height of the lamps from the ground is lower than the regulation 25m and other places that are more prone to electric shock, the lighting power supply voltage should not be greater than 36V.
In wet and easily accessible places with live bodies, the lighting power supply voltage shall not be greater than 24V.
In particularly humid, well-conductive ground, boilers or metal containers, and other places with a high risk of electric shock, the lighting power supply voltage must not be greater than 12V.
The running light voltage shall not be greater than 36V.
The lighting voltage offset value is up to -10% to 5% of the rated voltage.
4.Lighting fixture settings
1) Installation height: generally 220V lamps are not less than 3m outdoors and not less than 2 indoors5m;The installation height of iodine-tungsten lamps and other metal halide lamps should be more than 3m. The use of iodine-tungsten lamps is no longer allowed on the construction site.
2) Installation wiring: the center contact of the screw lamp head should be connected with the phase wire, and the screw mouth should be connected with the neutral line (connection: the lamp wire of iodine-tungsten lamp and other metal halide lamps should be fixed on the special binding post; The inner wiring of the lamp must be firm, and the external wiring must be reliably waterproof and insulated.