【 Weak current College 】 defense project of induced electrical fire and precautionary measures-Power By 【 China power house network 】

As defense project of peacetime continue in-depth and extensive exploitation, a large number of electrical equipment into the defense project, it works for people in the ongoing production and life offers great convenience. At the same time, improper use, maintenance, poor management, poor, owing to the protection, civil engineering, electrical fire occurred from time to time so that the country and the people's property and suffered a great loss of life. How to correctly analyze defense project internal electrical fire-induced causes, to develop reliable safeguards has become our reality and future defense project safe use and management of important research topic. This article on the way from electrical wiring and electrical equipment design, installation, maintenance, management and analysis, talk about defense project electric fire precautions.

? Why gas fire-induced

From electrical fire thrown onto the form, generally can be divided into four types. First, because the wire or equipment insulation damage or breakdown, phase

And phase, and short-circuit arcing between the ignition, or short circuit protection device failure, powerful short-circuit current so that the electrical equipment, electric circuit heating fires. The second is due to the electric lines, electrical equipment of leakage, overload, contact resistance is too large, three-phase motor power phase, the voltage is too high or too low, three-phase voltage unbalance, equipment in the fault State work and other factors, may cause electrical lines or electrical heating, even burn. If it happens such lines, equipment near flammable materials, a high risk of fire. The third is the heat of the lighting equipment and electric equipment close to combustible material, since the heat radiation fire ignition articles. There are four is flammable and explosive articles (especially with combustible gases) of the site due to electrical work, switch action contact spark ignition generated EDM, such as flammable materials in case of fire. Occurred in the four categories of electrical fires

The main reasons are the following.

(A) the design, the construction does not regulate or substandard, impacted problems

First, early construction defense project lighting wires used, many are aluminum wire. In accordance with the relevant information on the wire of the normal service life of only 7-8 years in a wet environment using 2-3 years, it will always fail. In particular in the connectors and wiring and electrical devices (copper and aluminum connectors), since the electrochemical reaction accelerated corrosion to contact resistance increases, produce local overheating damages insulation, cause joint loosening of spark, circuit, there is a fire burning items. Secondly, it is not according to relevant regulations laying lighting lines, or feel free to use in lamps, hot tubs and combustible materials, free to change small stuffing tube pipe. The former enables the conductors easily effect by the surrounding environment, which increase in accident rates so that the wire heats, allowed current-ratings of decline, the insulating layer of premature aging, brittle, the insulation resistance is reduced, resulting in an accident.

(Ii) assume nothing, neglect, lack of knowledge is power for the electric fire hazards

1, electrical wiring, electrical equipment not regularly maintenance; wire aging electrical equipment in a failed state; electrical protective equipment failure.

2, is not consistent with the practice for chaos, chaos electrician who received; non-electric; without an overhaul of the electrical system.

3, fuses the melt does not meet the requirements, or even using other conductor replacement, no proper protection.

4, article heap into excessive proximity lighting; at the power distribution unit, electrical rooms, electrical equipment in the vicinity of arbitrarily piled articles; not from the combustible items

There are certain safety distance, using thermal appliances. What is more, in the absence of any protective measures in place to store flammable or explosive substances.

5, small power cable-power loading. Electrical switching capacity, cable, wire and wire size is electrical designers depending on the load size. Project use function changes, the need to increase the capacity of the electrical equipment or the introduction of new electrical devices, if you do switch, line to check the blind received la, exceeding the rated operation, the switch, lines overheat, destruction of the insulation caused a short circuit, causing a fire.

These vulnerabilities are obvious, the prevalence is easy to work with units and managers neglect. Its origin is a project of the use, management, maintenance personnel lack of truly understand electrical technology and professional maintenance personnel, lack of electrical knowledge, and common sense, the lack of real fire to understand physics, electrical engineering technology professional maintenance personnel, the lack of power engineering and scientific, systematic and standardized management.

(3) subject to the influence of underground environment, electrical wiring, equipment gets wet submersible hidden under

This is the electric fire defense project, another key feature. Summer and autumn seasons project air humidity. As a result of condensation and mould, etc, often make the electrical equipment, metal Office shell corrosion shorten the service life, and as a result of condensation water penetration and spread into the insulator, especially the summer and autumn seasons project internal electrical wiring, electrical equipment, power distribution unit, extremely easy moisture corrosion, ranging from insulation performance, equipment performance, joint contact resistance increases, causing lines, equipment overheating, accelerated aging. To make insulating dielectric breakdown caused by leakage, grounding or short circuit between phases and even burning device ignition of flammable substances in case of fire.

(Iv) the quality of power supply, substandard equipment damage three-phase electric is hidden

We use the most is the motor, three-phase induction motor, in use, if the power supply appears phase, the voltage is too high or too low, three-phase voltage unbalance, not only motor not properly, will cause a loss, even burnt motor fires.

If the motor in operation, for any reason a phase (one phase disconnect two phase still pass phenomenon) motor continues to operate, the to markedly reduce the electromagnetic torque, rotational speed increases the rotor and the stator current, temperature rise, if not timely detection and immediately cut off power supply, motor has burnt the possible cause of electrical fires.

　　Power supply voltage is too high, motor stator current, not only to increase consumption and cause the motor to overheat; power supply voltage too low (motor torque and voltage proportional to the square), the motor torque, rotational speed decreased significantly decreases, increases the rotor and the stator current, high temperature, such as machine motor's torque below the load torque, the motor will suddenly stop working, if not cut off the power in a timely manner, or will burn electrical fire

Power supply for three-phase unbalance, causing three-phase current unbalance, if the deviation is greater than 10%, significantly reduce the motor torque, increases the rotor and the stator current, high temperature, severe cases machine will burn electrical fire.

Second, the defence of the electric fire precautions

Overview of the civil defense engineering electrical fire-induced causes the analysis, while special environment on the ground floor has a certain impact, but it is not the main reason, as long as the management and maintenance can cover and transformation of the. Ignore the electrical fire management, lack of the necessary rules and regulations, liability is not implemented, every year several security fire prevention inspections formality superficiality cannot persist, this is the electric fire defence lies. Historical experience, practice has shown that: If caught in the design, construction and acceptance on the three main components, strictly, in the management, maintenance, use of the work to enable; in advocacy, education, and outreach on often, can ensure the safe use of air defence project.

(A) the careful design, elaborate construction, strict acceptance is the preventive defense project the basic guarantee for electrical fires

The good design, the strict implementation of design specifications, the characteristics by underground copper conductors should be used, as far as possible, it is a good selection of moisture-proof electrical products, and transformation of engineering to use dry-type transformers, this is because oil-immersed power transformer coil short-circuit, causing the explosion fire, combustible transformer transformer insulating oil flows out of the fire. And dry-type transformers, low voltage windings A, B, C-line are made of epoxy resin casting, good insulation, moisture, and has several underground engineering using proven, safe and reliable. Electrical equipment should be installed in the project comparison dry, well-ventilated place. To avoid humid place, in a good operating environment.

Electrical design ceiling of distribution lines, try to wear pipe laying and lamps, hot tubs and other shareholder structure on both sides, to ensure a safe distance from the line Branch Office should be placed in the terminal box, combustible materials library, do not use halogen lamps and the bulk of the incandescent lamp (100 Watts) and other high radiation heat of luminaires. Diesel generator room, tank, battery set and other flammable gases room, to use airtight or explosion-proof lamps and a moist places within the project, lots of moisture-proof luminaires to consider.

(Ii) electrical design to carefully consider protection facilities

In lighting, power distribution box, fitted with leakage switch (protector). Lighting lines or lighting apparatus for moist insulation resistance drop, started to produce the leakage current, has installed a leakage switch, when leakage current reaches a certain value, automatically disconnect the circuit, so as to prevent short circuit caused by decreased insulation fire. Electric lighting, distribution and other overhead transmission lines with the introduction of engineering should be installed on the outside of the arrester. Works within distribution cabinet (tray), electric equipment, should adopt a sensitive and reliable measures of protection of zero. Design-phase load to uniform maximum of not more than 10%. Project for use in a three-phase induction motor to press for retrofitting short circuit, phase, overload protection, network voltage instability (too high or too low) exceeds allowed value that you want to install regulators or protector. To avoid burning of motor evoked a fire.

(C) construction, strict implementation of national and industry issued by the relevant standards and specifications

Can not arbitrarily reduce conductor nominal cross-sectional area, small stuffing tube diameter. The laying of lines required by statutes, installation equipment, connectors to splicing laminate, bandaging dense. It should be noted that the lamp, ballast and fuel between certain safety distance, when using halogen lamps and incandescent places with large capacity, it is necessary to take the ventilation, thermal insulation and fire protection measures. Halogen lamps and incandescent large empty content, using ceiling trough installation power supply inlet to wear porcelain tube introduced, at the same time and fuel near Department, made of non-combustible materials such as asbestos insulation.

In electrical equipment put into operation, in strict accordance with the acceptance procedures and relevant technical standards for acceptance, fake or substandard electrical equipment must be replaced, unqualified installation to resolutely rework. Acceptance, on the lamps installed wiring connector and other random checks, to ensure that their number and increase cover face important parts are individually inspected, one at acceptance, on the protection of the system to carry out experiments or tests.

(Iv) strengthen management, Jianzhang formed, implement responsibility is preventive defense project, the only way for electrical fires

Develop practical management, maintenance measures, establish and improve electrical maintenance management regulations is defense engineering maintenance management into scientific, systematic and standardized only way, but also to eliminate potential electrical fire defence of fundamental guarantee. Practice has proved that it is necessary to set in large engineering professional maintenance personnel, for small projects to organizations with expertise and technical staff carry out regular inspections and maintenance of the tour.

Project use, to ensure that motor, power distribution cabinet (a) the room should have good ventilation, and maintain the proper temperature and humidity, nearby flammable materials cannot be stacked. On long-term unused distribution cabinet (tray), motor, electrical equipment, usage before testing and inspection. If the equipment insulation resistance meets the requirements. The regular use of electrical equipment should also be periodic testing. In the early defense project, the use of wood joist, CA plastic Board, fibreboard and other inflammable materials do hanging decoration items, use the corresponding lamp parts in regular checks, in the event of electrical failures to the timely removal of timely maintenance. If necessary, should be local, eliminate fire hazards.

Projects usually use to clear, for it is used, the electric capacity and transferred to the appropriate line loadThe whole. Necessary to increase the distribution lines and power capacity. New uses of works to think electric equipment, line load, insulation level for identification, full or partial modification of the decision. Additional electrical equipment and increase the load, on line and switches, protective device from new accounts. Every spring is to check the grounding equipment grounding resistance meets the eligibility requirements, lightning arrester, does not meet the requirements of timely repair or replacement.

Civil Defense underground power station, the transformer room and other important places for the greater electrical fire danger, fire and maintenance to focus, and transformation room, engine room, depots, warehouses, engineering mouth and the electrical equipment in the vicinity of the prohibition of storage of flammable or explosive substances, and should be set sufficiently for fixed fire-fighting equipment and fire-fighting tools. Strict enhanced oil and flammable materials management, computer rooms, smoking and open fires fuel depot as fire, water, gasoline, bananas shall be brought into the project, the work and maintenance needs to be taken security measures.

3. to strengthen leadership advocacy for improving quality is a preventive defense project long-term measures electrical fires

Engineering units and management unit of the main responsible for this work to dare, starting from the legal system, to develop the necessary regulations and the regulations. On the use, management, and several links clearly stipulated, rule-based, integrated into the fire safety and management of the rail, adhere consistently to prevention, anti-binding approach, establishing fire brigade, set the full-time and part-time and, firefighters. Accept the Fire Department of formal training, implementing a fire safety system, enhanced accountability and fire protection, fire-fighting capability. Education for all (EFA), the safe use of electricity of common sense, common fire-fighting equipment, usage, on staff at the hospital, the initial fire knowledge self-help remedy knowledge as ground staff of an appraisal standards. The underground staff not only know how to safe use of electricity, fire, and once a fire has certain fire fighting, the ability to help themselves, redress. The minimal losses.

Periodic checks are leadership, management authorities do a fire, effective means of eliminating dangers. In fire-prone season, the annual new year's day in early summer, national day, and before the Spring Festival, issuing the security check layout of specific interests, organize the relevant departments of the joint inspection, the personnel-intensive sites and important goods warehouse, in conjunction with the police, fire departments for focus checking and found that the accident risk, timely issued rectification notices corrected, and do a review

To sum up, the electric fire defense project because although there are many induced, but its fundamental only eight characters "of regulations, management is not strict," especially with the deepening of China's reform and opening up, the development and use of Defense project into a market economy, the project's use, managers must not only focus on economic efficiency, neglect of fire safety, do not have numbness, luck. In the event of an accident, would cast Rue. To on the one hand and economic, on the one hand and security, efficiency and security. Electric fire is not the background, as long as the preventive chapter formed in do build, strictly, universal education, and unrelenting efforts to significantly reduce or eliminate the risk of electrical fires, electrical fire away. At the same time, also requires the use of civil defense works, management of leader do three words; one is the "truth", is truly electric fire protection measures are implemented; the second is the "House" is in electrical maintenance, electrical fire facility willing to invest. Willing to spend effort; third, "long" in electrical fire prevention education, layout check on durable frequently; this is an electrical fire defense project.