As we all know, when cables are aging for household or commercial use, if businesses continue to use them, it is easy to cause danger. But how to check whether the wire is aging still needs some technology.
The wire is mainly insulated by a layer of outer sheath. After a long time, it is corroded by corrosive gas. The insulation performance is gradually reduced, and then it becomes hard and brittle or falls off. At this time, it will not play the role of insulation. In fact, the direct cause of aging failure of wires and cables is the breakdown due to the reduction of insulation. Jin Huanyu wire and cable editor teaches you two points: how to judge whether the wire is aging, check it in time, and put an end to potential safety hazards.
Follow the wire to check the appearance, darken and crack. Both hands are curved and insulated, with rigid and cracked skin It refers to the observation of the insulating layer along the conductor. If the insulating layer is found to be tarnished, darkened, hard, cracked or partially peeled off.
When the insulated conductor is bent with both hands, the conductor is rigid, even the insulating layer is cracked, and the insulating layer falls off, which indicates that the conductor has been aged and seriously aged in different degrees.
Accurately measure the insulation with two megohm low points. In rainy days, the humidity value can be small, and the value can be half smaller. " It means that the insulation measurement of electric lines can be made by using insulation resistance meter to judge the insulation condition of lines accurately.
The insulation of different lines has different allowable values. For example, the insulation resistance of the household 220 V line in use shall not be less than 0.22 megohm; the humidity value in rainy days shall not be less than 0.1 megohm. If the measured insulation resistance value is less than the above value, it indicates that there is a problem in the insulation of the electrical line. Of course, under different use conditions, the service life of the cable is different, which needs to be handled according to the situation.
