In the field of electrical safety, the American UL (Underwriters Laboratories Inc.) standards hold a crucial position, with its recognized safety certification system having a global influence. Among the various UL standards, UL651 specifically sets out detailed requirements for PVC (Polyvinyl Chloride) electrical conduits and fittings. This standard covers four different types of rigid PVC electrical conduits and their accessories: Schedule 40, Schedule 80, Type EB, and Type A, ensuring the safety and applicability of these products in various usage environments.

1, Mechanical strength: The conduit must undergo tensile strength, bending, compression, and impact tests to ensure it does not easily break or deform during installation and use, and maintains structural integrity even in harsh environments.

2, Flame retardant performance: Considering the risk of fire, PVC conduits must pass combustion tests to verify their flame retardancy, reducing the likelihood of fire spread and protecting lives and property safety.