【 Weak current College 】 Emporium electrical wiring design requirements

With the rapid development of market economy, various shopping centres tend to be large-scale, integrated, a sharp increase in the number, scale is continually expanding, at the same time, the shopping centre market fire frequency has been increased to life and property caused serious damage. As a result, personnel are crowded, the building of larger large shopping malls, the fire-fighting equipment of electric wiring should have reliability, fire resistance, safety, efficacy and scientific aspects of higher demand. Currently existing national norms on fire electric equipment of power supply system design made clearer provisions and requirements, relatively speaking, on fire with electrical equipment and electric power distribution line of fire safety requirements require less, according to the combination of large shopping centres, the fire safety requirements for large shopping centre, fire-fighting equipment distribution line selection, installation, fire performance requirements for the design and initial discussion.
1. fire-fighting equipment distribution line features
Fire-fighting equipment requirements of distribution line is determined by its power of decision, a request which mainly fire equipment power supply line reliability and power of fire, the fire resistance of the electrical circuit. Fire distribution line reliability mainly refers to the fire, particularly in the early stage of fire and extinguishing with high reliability, including the usual run of reliability in the process, to ensure that the normal power supply and fire can effectively implement evacuation and fire fighting, fire loss is reduced to a minimum. Fire on fire renewable power distribution lines, and also can be understood as the reliability of fire power distribution lines, is used to ensure that in the event of fire and fire power distribution lines may be in the fire, will necessarily require continuous power to implement effective grooming and initial fire suppression.
Second, a large shopping centre, various types of fire power equipment line fire design analysis
(1) automatic fire alarm system of electric distribution lines
Automatic fire alarm system is an important facility fire prediction, for early detection of fire and extinguishing the fire early timely plays a very important role. Because of its role mainly in non-fire, and fire at an early stage, so the automatic fire alarm system electrical circuit of the extension part of the best use of flame retardant wire wear protection pipe laying in the combustible structure layer (cover thickness greater than 30mm), the current common bus system, fire alarm system of trunk, because a loop of trunk line is long, often across different fire partitions, and more for the downlead, once the mains failure will result in the main loop of all monitoring stations in monitoring State. Therefore need higher requirements, such as the use of fire-resistant cable laying in the fire-resistant cable tray, there is a condition of using steel skin protection mineral insulated cable.
(2) fire hydrant pump, spray pumps and power distribution lines
Fixed water fire extinguishing facilities fire hydrant system booster pumps, water spray system booster pumps, water curtain system booster pumps, fire pumps is the main implementation of fire fighting equipment. The fire pump is working properly or not directly related to the fire suppression effect, its distribution lines of fire design should give special attention. The fire pump General focus settings in the pump house, its distribution lines include dual power or double loop power lines and water pump motor power distribution extension, typically pump motor installation methods of distribution lines may be wearing protective tube and placed in layers of combustible structure, or cable bridge overhead downlead, such as selection of fire-resistant cable is better equipped to fire-type cable bridge, to increase the electrical circuit of the heat-resistant. While pumping supply power from shopping malls to provide direct, substation substation and pump house with adjacent or are more recent, and belong to the same fire partitions, you can use fire-resistant cables or refractory bus along fire-type cable bridge downlead, substations and pump house farther apart (e.g. through different fire partitions), you should use copper Peel fire-type cable power supply.
(3) smoke control equipment
Smoke control device is the Arcade Fire prevention is important, it includes positive-pressure blowers, smoke machine, all kinds of valves, fire valves, etc., these devices working properly or not directly related to evacuation and can effectively prevent the fire from spreading.
Because smoke installations layout general comparative dispersion, so its electrical circuit design to consider supply main loop line, also taking into account the linkage control lines. In view of the flame retardant cable in the face of the open fire, the electrical insulation properties rapidly decreasing, smoke control equipment distribution lines when the downlead should use fire-Crosslinking low voltage cables or copper Peel fire-cable, but concealed, choose General fire-resistant cables, linkage and control line should use fire-resistant cable. In addition, smoke control equipment distribution lines and linkage control lines in laying the line length should be as short as possible, and avoid passing through different fire partitions.
(4) fire shutter distribution line
In the large shopping area of each layer are often very large, and at the same time, the atrium and from top to bottom through the escalator, the use of fire shutter will be different for fire compartmentation, blocking the spread of the fire separation. Fire shutter effect of isolating the fire is built on a reliable power supply via power distribution lines to make fire shutter on the basis of effective action. In General, the power of fire shutter can be cited from the shopping centre in layers with dual power switching power distribution box, fire shutter dedicated distribution box to fire shutter control box power supply, power supply mode for the use of radial or ring. Usually for ease of installation, maintenance, distribution lines and to have fire-resistant and heat-resistance properties, when fire shutter level distribution lines long date using fire-resistant cable and ceiling using fireproof cable tray out enough to ensure that the fire occurred and caused the indoor temperature rise still reliable power supply and fire protection shutter effective landing, prevent the spread of fire.
(5) fire lift power distribution lines
Fire evacuation elevator is and fire fighting with important tools, distribution line fire design should be compatible with this feature. According to the current instance of the fire protection engineering, fire lift power is normally provided by the Mall distribution room green power distribution to the laying of the circuit is located in the top-level elevator machine room, causing a fire service lift distribution line is generally relatively long, and the lines are more complex. Therefore, in order to improve reliability, the fire service lift power distribution lines should be fire-resistant cables, when there are special requirements on reliability, two roadThe way of distribution line may use copper Peel fire-type cable. Specification to lift power lines should not be laying in the elevator shaft road, fire service lift distribution line laying in shopping centres set up electrical shaft.
(6) of the fire emergency lighting distribution line
Fire emergency lighting's role is to ensure the fire officer ordered the evacuation and fire officers continue to work, it includes evacuation instructions lighting and alternate lighting. In General, evacuation instructions lighting and fire lighting, emergency lighting battery, or you can force the restart point of general lighting lamps, and alternate lighting switch using dual power to achieve or supposes emergency power supply. Therefore, the fire emergency lighting line generally use retardant wire wear steel pipe protection dark laying in the combustible structure layer, decoration engineering, structural engineering may encounter construction was completed, the emergency lighting line cannot be concealed in the structural layer, but only within the downlead suspended ceiling, in order to meet fire protection requirements, electrical line should use heat-resistant type or refractory material, take fire prevention measures. In summary, the major shopping malls of fire fighting equipment electrical wiring is important throughout the fire protection system, complete content shall be considered in conjunction with the actual fire-resistant requirements and select the electrical wiring, in order to increase reliability of power supply of fire protection equipment and fire resistance.