How to judge whether a cable is qualified?

Qualified cables are the premise of safe power transmission and use. For engineers, contractors and importers, mastering simple methods to judge whether cables are qualified can effectively avoid purchasing unqualified products and reduce potential safety hazards. The following are several easy-to-operate judgment points. 

·Check the surface of the cable. Qualified cables have clear and standard specifications, brand marks, production date, and other information on the surface, which is not easy to fade or wipe off. Unqualified cables often have blurred marks or even no relevant marks.

·Observe the internal structure. After stripping the sheath, the conductor of the qualified cable is smooth and uniform, free of burrs, oxidation, and other phenomena; the insulation layer is uniform in thickness, firm in texture, and has no bubbles, cracks, or other defects, which can effectively isolate the conductor. 

·Confirm the factory test report. Qualified cables must pass professional voltage resistance, insulation, and other tests before leaving the factory, and have a complete test report. When purchasing, you can ask the supplier for the test report to verify the qualification of the cable.