Photovoltaic cables are often exposed to sunlight, solar energy systems are often used in harsh environmental conditions, such as high temperature ultraviolet radiation. In Europe, sunny terrain will result in on-site temperatures of up to 100°C for solar systems. Now, we can use a variety of materials such as PVC, rubber, TPE and high-quality cross-linking materials. The characteristics of photovoltaic cable are selected by its cable special insulation material and sheath material, we call it crosslinked PE, through the irradiation accelerator irradiation, the molecular structure of the cable material will be changed, and then supply its aspects of function. Resistance to mechanical load, in fact, during equipment and maintenance, the cable can be routed on the sharp edge of the roof structure, together with the cable must withstand pressure, bending, tension, cross-tensile load and strong impact. Assuming that the strength of the cable sheath is not possible, the cable insulation layer will be severely damaged, and then affect the service life of the entire cable, which may lead to problems such as short circuit, fire and personnel hazard. So choose the use of external environment must use TUV EN50618 photovoltaic cable.