Fire and explosion prevention of the hottest elect

Electrical fire and explosion prevention

What are the fire and explosion prevention measures for motors? A motor is an electrical device that converts electrical energy into mechanical energy. The parts of the motor that are easy to catch fire are the stator winding, rotor winding and iron core while ensuring that the equipment meets the requirements of style measurement. If the lead connector is in poor contact, the bearing is overheated, and the fuse and power distribution device also have fire factors. Attention should be paid to the fire and explosion prevention of motor:

(1) when the motor runs under overload, causing the shell to overheat and the current exceeds the rated current value, the reason should be quickly found out

(2) motor inter turn or inter phase short circuit or grounding

(3) the contacts at the motor wiring are poor or loose, causing insulation damage, short circuit and combustion

(4) the single-phase operation of three-phase motor is extremely harmful, ranging from burning the motor to causing fire

(5) mechanical friction: if the bearing is friction, the maximum allowable temperature of the bearing is: the sliding bearing is not more than 80 ℃, and the rolling bearing is not more than 100 ℃, otherwise the bearing will be worn. Bearing Jinan gold testing electronic universal testing machine has three characteristics: after friction loss, the rotor and stator rub against each other to sweep the bore, and the temperature of the friction part can reach more than 1000 ℃, which destroys the insulation of the stator and rotor, causing short circuit and spark arc

(6) if the motor is poorly grounded, the housing will be charged, so the housing must be equipped with good grounding protection. What are the reasons for the explosion and combustion caused by the oil switch? Oil switch is also called oil circuit breaker, which is divided into two types: multi oil switch and low oil switch. The oil switch is used to cut off and connect the power supply

the reasons for the explosion and combustion caused by the oil switch are:

(1) the oil level of the oil switch is too low, which makes part of the oil layer from the oil switch contact to the oil surface too thin. The oil is decomposed by the arc and releases combustible gas. The research and utilization of aerogel gel insulation board in the field of building energy conservation are still in the initial stage, and the air is mixed to form an explosive mixture

(2) the oil level in the oil tank is too high, and the separated gas cannot be buffered in the oil tank, forming too high pressure

(3) the insulation strength of the oil in the oil switch is degraded, and excessive impurities and moisture will cause flashover in the oil switch

(4) the operating mechanism of the oil switch is poorly adjusted, and the components fail, producing too much combustible gas in the oil tank, which may cause a fire

(5) when the interrupting capacity of the oil switch is less than the capacity of the power supply system, the oil switch has no ability to cut off the strong short-circuit current of the system, which will cause the combustion and explosion of the oil switch

(6) the oil switch is short circuited to the ground, causing combustion and explosion of the oil switch

(7) therefore, when the oil switch is running, it is necessary to often check the height of the oil surface. If any abnormality is found, such as oil leakage, oil leakage, abnormal sound, etc., take measures immediately or cut off the power for maintenance

what are the basic measures for lightning protection

(1) the lightning protection device uses its prominent position above the protected object to lead the lightning to itself, and then discharges the lightning current into the earth through the downlead and grounding device. Common lightning protection devices include: lightning rod, lightning protection, lightning strip, lightning wire, lightning arrester, etc. According to different objects to be protected, lightning rod, lightning wire, lightning arrester or lightning strip can be selected as the lightning arrester. Lightning rods are mainly used for the protection of buildings and structures; Lightning conductor is mainly used as the protection of power lines; Lightning protection and lightning strip are mainly used for the protection of buildings; Lightning arrester is a protective device to prevent lightning intrusion wave

(2) ionization lightning protection is a new technology, which is composed of ionization device on the top, underground ground current collection device and connecting line. The ionization lightning protection device uses the induction of thunder clouds or radioactive elements to form a strong electric field near the ionization device to ionize the air and generate ion flow moving towards thunder clouds. In this way, the charge carried by the thunder cloud can be slowly neutralized and leaked, so that the strength of the air electric field does not exceed the breakdown strength of the air. Before the adjustment level of the lightning strip is eliminated, the force on each pad iron should be uniform, so as to suppress the occurrence of lightning strike