ETFE Insulated Wire

Function: Conductor is a component of a wire and cable that transmits electrical (magnetic) energy, information and realizes specific functions of electromagnetic energy conversion.

Material: There are mainly uncoated conductors, such as copper, aluminum, copper alloy, aluminum alloy; metal-coated conductors, such as tinned copper, silver-plated copper, nickel-plated copper; metal-clad conductors, such as copper-clad steel, copper-clad aluminum, aluminum clad steel, etc.

Function: The insulating layer is wrapped around the conductor or the additional layer of the conductor (such as refractory mica tape), and its function is to isolate the conductor from bearing the corresponding voltage and prevent leakage current.

The commonly used materials for extruded insulation are polyvinyl chloride (PVC), polyethylene (PE), cross-linked polyethylene (XLPE), low-smoke halogen-free flame retardant polyolefin (LSZH/HFFR), fluoroplastics, thermoplastic elasticity (TPE), silicone rubber (SR), ethylene propylene rubber (EPM/EPDM), etc.

Function: The shielding layer used in wire and cable products actually has two completely different concepts.

First, the structure of wires and cables that transmit high-frequency electromagnetic waves (such as radio frequency, electronic cables) or weak currents (such as signal cables) is called electromagnetic shielding. The purpose is to block the interference of external electromagnetic waves, or to prevent the high-frequency signals in the cable from interfering with the outside world, and to prevent mutual interference between wire pairs.

Second, the structure of medium and high voltage power cables to equalize the electric field on the conductor surface or the insulating surface is called electric field shielding. Strictly speaking, the electric field shielding does not require the function of “shielding”, but only plays the role of homogenizing the electric field. The shield that wraps around the cable is usually grounded.

Electromagnetic shielding structure and materials

① Braided shielding: Mainly use bare copper wire, tin-plated copper wire, silver-plated copper wire, aluminum-magnesium alloy wire, copper flat tape, silver-plated copper flat tape, etc. to be braided outside the insulated core, wire pair or cable core;

② Copper tape shielding: Use soft copper tape to cover or wrap vertically outside the cable core;

③ Metal composite tape shielding: Use aluminum foil Mylar tape or copper foil Mylar tape to wrap around or vertically wrap the wire pair or cable core;

④ Comprehensive shielding: Comprehensive application by different forms of shielding.For example, wrap (1-4) thin copper wires vertically after wrapping with aluminum foil Mylar tape. The copper wires can increase the conduction effect of the shielding;

⑤ Separate shielding + overall shielding: Each wire pair or group of wires is shielded by aluminum foil Mylar tape or copper wire braided separately, and then the overall shielding structure is added after cabling;

⑥ Wrapping shielding: Use thin copper wire, copper flat tape, etc. to wrap around the insulated wire core, wire pair or cable core.

The function of the sheath is to protect the cable, and the core is to protect the insulation. Due to the ever-changing usage environment, usage conditions and user requirements. Therefore, the types, structural forms and performance requirements of the sheathing structure are also varied, which can be summarized into three categories:

One is to protect the external climatic conditions, occasional mechanical forces, and a general protective layer that requires general sealing protection (such as preventing the intrusion of water vapor and harmful gases); If there is a large mechanical external force or bear the weight of the cable, there must be a protective layer structure of the metal armor layer; the third is the protective layer structure with special requirements.