Fire prevention measures for the hottest electrica

Fire prevention measures for electrical equipment

the fire caused by the failure of electrical equipment is unimaginable, and sometimes a large number of electrical appliances will be burned down, and even electric shock casualties will occur. Therefore, the causes of electrical fire must be carefully analyzed

1 fire prevention measures caused by transformer fault

the cause of the fault is caused by serious overload operation, short circuit due to coil insulation damage, transformer oil aging, excessive contact resistance at the connection or tap, failure of high and low voltage fuses to fuse during short circuit of external lines, iron core damage, arc flashover in oil, lightning strike and other reasons. As the transformer is filled with insulating oil, the consequences of fire are very serious. When the fifth experiment is completed, the oil is sprayed and ignited, and the internal pressure of the transformer rises sharply due to the decomposition and gasification of oil, causing the shell to burst and a large number of oil leakage and combustion. The preventive measures are:

(1) the power transformer should be equipped with fuses or relay protection devices, and when the capacity is large, it should also be equipped with gas relays, so as to cut off the fault transformer and electricity in time

(2) strengthen insulation monitoring, and regularly conduct preventive test and rotation maintenance of transformer insulation

(3) manage the insulating oil well. If the oil is aging, water enters and the insulation strength is insufficient, filter the oil or replace it with qualified new oil

(4) the transformer should be installed outdoors or in buildings with class I and II fire resistance rating, and should be well ventilated

(5) strengthen operation management, and often monitor the load of the transformer during peak load hours. If overload is found, take measures to transfer the load or replace it with a transformer with larger capacity

(6) regularly check whether the lightning arrester works normally, and replace the unqualified products in time

(7) promote the application of fully sealed power transformers. For high-rise buildings, where they are increasingly subject to innovative research and development of cutting-edge products and technologies, and especially important places, dry-type transformers or box type substations with flame retardant or self extinguishing performance should be selected

2 fire prevention measures caused by line fault

the cause of the fault is caused by overload, short circuit and excessive contact resistance at the connection of the electrical line. The excessive current of the line causes serious heating, destroys the insulating materials and burns, and sometimes electric sparks will occur, causing nearby inflammables to catch fire. In addition, the wrong line is connected during road maintenance. For example, connecting a 220V circuit to a 380V circuit, or breaking the high-voltage line, and touching the low-voltage line will also cause a fire accident. The preventive measures are as follows:

(1) to prevent serious overload of the line, reasonably select the conductor section according to the actual load in the circuit

(2) correctly select the rated current of the automatic circuit breaker or fuse, which should match the safe current carrying capacity of the wire, and it is not allowed to use copper wire to replace the fuse. For the old style knife switch with rubber cover, the connection of high current fuse is often difficult to tighten, resulting in arc or spark, which is very unsafe

(3) qualified electricians should install the lines, and it is not allowed to pull and connect the waste wires privately. The joints in the circuit must be spliced according to the regulations to make the contact good. There must be no joints in the wires passing through the pipe. The indoor and outdoor wire connections shall be wrapped with insulating tape and shall not be damaged or exposed

(4) the terminals and intermediate joints of cable lines at the construction site should comply with the requirements of the specification, and should not exceed the length required by the specification. For high-rise plastic packaging and printing enterprises facing severe challenges, buildings or other important places with dense crowds should choose cables with good flame retardant performance

(5) copper aluminum transition joints should be used for the outgoing line and connection of aluminum wires and electrical equipment, and the ones with small current should also be in good contact, so as to prevent poor contact due to the oxidation of aluminum surface

(6) there should be sufficient safety distance between bare conductors and between live parts and grounding parts. The conductor should not be too loose when hanging overhead, so as to avoid short circuit of the conductor when the wind blows

3 fire prevention measures caused by motor failure

the cause of the failure is caused by long-term overload operation, inter turn or inter phase short circuit due to winding insulation damage, power failure of one phase of three-phase motor, shaft seizure caused by motor mechanical component failure, and the combustion of flammable substances caused by brush sparks on the opposite side of gb/t 3104 ⑴ 982 fastener 6 corner products, The preventive measures are as follows:

(1) the type selection of motor should comply with the fire safety grade. Closed motor should be selected in humid and dusty environment, and explosion-proof motor should be selected in flammable and explosive environment

(2) the motor should be installed on a non combustible base, and the surrounding should be kept at a distance of more than 1m from combustibles, and sundries should not be stacked

(3) each motor must be installed with a separate switch and a suitable fuse as overload protection, and the three-phase motor with large capacity should be installed with a protective device to prevent one phase power failure and two-phase operation

(4) strengthen the repair and maintenance of the motor, add lubricant to the bearing frequently, and replace the brush frequently. Pay attention to whether the temperature is too high or there is spark

(5) the starting times of the motor should not be too frequent, especially in the hot state, the continuous starting times should not exceed 1 ~ 2 times, the starting time should not be too long, and long-term overload operation is not allowed

(6) the power supply voltage of the motor should not be too high or too low. If abnormal phenomena are found, the cause should be found out. The power supply should be disconnected immediately after the motor is stopped and used

4 fire prevention measures caused by lighting fixture failure

the cause of the failure is the fire caused by the electric spark of the installation of ordinary lighting fixtures in places with inflammable and explosive gases, the fire caused by the loosening of the screw head and central tongue of incandescent lamps, the fire caused by the replacement of bulbs, the loose plug and the loose connection, and the fire caused by the loose connection. In addition, the damaged or too long monitoring wire may also cause the fire. The preventive measures are as follows:

(1) choose different electric lamps according to different electric fields. Explosion proof lamps should be used in inflammable and explosive places

(2) a certain safe distance should be kept between the bulb and the combustible, and it is not allowed to be close to the combustible

(3) fluorescent lamps should not be installed close to combustible ceilings

(4) unplug the plug in time when household appliances are out of service. At the same time, the plug and wiring shall be soldered

(5) select appropriate leakage protector and inspect it regularly

(Wang Min)