6.35/11Kv 3 Core Fire Resistant Medium Voltage Cable

A:  The flexibility of cables depends on many factors, including their structure, material, design, and application scenarios. Cables with good flexibility are easier to bend and lay during installation, and are suitable for applications that require frequent movement or bending, such as robots, industrial automation, drag chain systems, and outdoor mobile equipment.

A:  The lightning protection performance of medium-voltage cables is relatively good, especially under reasonable design and installation conditions, it can effectively resist the direct and induced impact of lightning. Medium-voltage cables are commonly used in power transmission systems with voltage levels of 6~35kV. Medium-voltage cables have metal shielding layers, metal sheaths (armor layers) and high-quality insulation layer materials. The shielding layer and sheath of medium-voltage cables usually need to be connected to a reliable grounding system so that when the induced current is generated by lightning, it can be quickly introduced into the ground. In important medium-voltage distribution systems, it is usually used in combination with overvoltage protection devices such as lightning arresters. The laying method of medium-voltage cables will also affect their lightning protection performance. Medium-voltage cables laid underground are usually shielded by the soil, and the probability of being directly struck by lightning is low. Therefore, underground laying has a natural advantage in lightning protection. Overhead medium-voltage cables may require additional lightning protection measures, such as equipping lightning rods and erecting lightning conductors to reduce the risk of direct damage caused by lightning strikes. Medium voltage cables have stronger lightning impulse resistance. After special treatment, these cables can withstand higher lightning current impulses and are not prone to cable aging or breakdown due to voltage transients. Lightning impulse resistance design is particularly important in applications in some high-lightning areas, such as coastal areas, mountainous areas and high-altitude areas.

A: To avoid short circuits in cables, we can start from the selection, installation, protection measures and daily maintenance of cables. We can select voltage level matching, correctly select the cross-sectional area of ​​cables according to load current, and select heat-resistant, corrosion-resistant, wear-resistant, or armored cables in places with high temperature, high humidity, corrosion or mechanical impact. This can effectively reduce the damage to cables caused by external factors, thereby preventing short circuits. Ensure standardized cable installation. Try to avoid laying cables in humid, corrosive, or high-temperature areas. Avoid excessive bending or stretching of cables during installation. Ensure that cables are not scratched by sharp objects to reduce mechanical damage during installation and use. For cables that may be damaged by external forces, such as buried or overhead cables, it is recommended to use protective tubes or cable ducts to enhance protection. Avoid cables being too close to high-temperature equipment or flammable and explosive materials, and ensure that there is sufficient spacing during installation to reduce the impact of high temperature and fire on cables. Installing suitable circuit breakers or fuses at the incoming or load end of the cable can quickly disconnect the circuit when a short circuit occurs to protect cables and equipment. Use professional connectors: Cable connectors are common locations for short-circuit accidents. Connectors that match the cable specifications and types should be selected to ensure that the connectors are tightly connected and have good conductivity. Regularly test the insulation resistance of cables, especially high-voltage cables. Insulation resistance testing can detect aging or damage to the insulation layer in advance. A humid environment can easily cause the insulation layer of the cable to age and crack. Ventilation and moisture-proof measures should be taken, especially for cables in underground or confined spaces. Overloaded cable operation will cause temperature rise, insulation aging, and increase the risk of short circuits. Therefore, the load should be distributed reasonably to avoid long-term high-load operation.