Frequently Asked Questions (FAQ)

• Q: What is the primary application of the Type YUHKGXSekyn cable?

  
  A: It is specifically designed for underground mining power networks with a nominal voltage up to 6 kV, particularly in hazardous zones such as methane and coal dust environments.

• Q: What voltage ratings does this cable support?

  
  A: The cable is rated for 3.6/6 kV operations, making it suitable for medium-voltage mining installations.

• Q: What type of conductor is used in this cable?

  
  A: It uses multi-stranded, round copper conductors that meet Class 2 standards as per EN 60228, ensuring excellent electrical conductivity.

• Q: How is individual shielding implemented in the cable?

  
  A: Each conductor is wrapped with its own shield, which can be made from conductive tape or conductive polyethylene combined with copper tape, minimizing interference.

• Q: What additional shielding does the cable feature?

  
  A: In addition to individual shields, an overall copper tape shield is applied around the cable for enhanced protection against external electrical disturbances.

• Q: What insulation material is used, and why is it beneficial?

  
  A: The cable uses cross-linked polyethylene (XLPE) insulation, which offers high thermal stability, excellent electrical properties, and mechanical strength.

• Q: How does the cable prevent moisture ingress?

  
  A: A longitudinal sealing tape that swells when exposed to water is applied along the cable, ensuring effective moisture protection.

• Q: What materials are used for the inner and outer sheaths?

  
  A: The inner sheath is made from PVC (Type DMV 31), and the outer jacket is a flame-retardant, tire-type PVC that minimizes flame spread.

• Q: Which standards does the cable comply with?

  
  A: It meets the ZN-TF 203:2006 standard and complies with relevant IEC standards for flame retardancy and performance.

• Q: Is the cable suitable for use in hazardous mining environments?

  
  A: Yes, it is approved for hazardous areas, including methane and coal dust explosion risk zones, ensuring safe operation in challenging conditions.

• Q: What is the maximum operating temperature of the conductor during normal conditions?

  
  A: The conductor can safely operate at temperatures up to +90°C under normal conditions.

• Q: How does the cable perform under short-circuit conditions?

  
  A: During short-circuit events, the conductor temperature may reach up to +250°C, demonstrating its robustness in fault conditions.

• Q: What are the minimum ambient temperature requirements for installation?

  
  A: For permanent installations, the cable can be laid at ambient temperatures as low as –30°C, and down to –50°C when laid without preheating.

• Q: What is the recommended minimum bending radius?

  
  A: The cable should not be bent tighter than 12 times its external diameter, ensuring the internal components are not stressed.

• Q: What high-voltage test does the cable undergo?

  
  A: The cable is tested at 15 kV AC for 5 minutes at 50 Hz to verify its insulation integrity and overall performance.

• Q: How is the cable’s tensile strength defined?

  
  A: The maximum pulling force is rated at 50 times the sum of the conductors’ cross-sectional areas, ensuring it can withstand the rigors of mining installations.

• Q: How does the outer PVC jacket enhance safety?

  
  A: The flame-retardant PVC outer jacket is designed to inhibit flame propagation, crucial for maintaining safety in explosive atmospheres.

• Q: What range of conductor sizes is available?

  
  A: Conductor sizes vary from 3x25/25 mm² to 3x240/30 mm², offering flexibility for different current-carrying requirements.

• Q: Are custom packaging options available for this cable?

  
  A: Yes, while standard packaging is available in 500 or 1000-meter drums, custom lengths and packaging options can be arranged as needed.

• Q: What is the purpose of the individual shielding on each conductor?

  
  A: Individual shielding minimizes electromagnetic interference and enhances operational safety, particularly in electrically noisy mining environments.

• Q: What is the function of the overall copper tape shield?

  
  A: The overall shield provides an extra layer of protection against external disturbances and further secures the cable’s electrical performance.

• Q: How is the cable’s current-carrying capacity affected by ambient temperature?

  
  A: The cable’s current-carrying capacity is derated for ambient temperatures above +25°C using specific correction factors (Kt).

• Q: What correction factors apply when multiple cables are installed together?

  
  A: When cables are laid in parallel or stacked, correction factors (Kg) are used—for instance, 1.00 for one cable, 0.93 for two, 0.90 for three, and so on.

• Q: How does the cable perform in high humidity or wet conditions?

  
  A: The combination of robust insulation, moisture-resistant sheathing, and longitudinal sealing ensures reliable performance even in high humidity or wet environments.

• Q: Is the cable RoHS compliant?

  
  A: Yes, it is RoHS compliant, which means it meets the necessary environmental standards regarding hazardous substances.

• Q: What are the cable’s typical electrical parameters such as inductance and reactance?

  
  A: For example, a 25 mm² conductor typically has a unit inductance of 0.32 mH/km and a reactance of 0.101 Ω/km, although these values vary with conductor size.

• Q: Why is XLPE insulation preferred for mining cables?

  
  A: XLPE provides excellent thermal, mechanical, and electrical performance, making it ideal for the demanding conditions in mining operations.

• Q: How does the cable ensure safety in explosion-prone environments?

  
  A: Its flame-retardant outer sheath, combined with robust construction and proper shielding, minimizes the risk of fire and explosion in hazardous atmospheres.

• Q: What details are available regarding the cable’s physical dimensions and weight?

  
  A: The cable’s overall diameter, weight per kilometer, and insulation thickness vary depending on the selected conductor size, with detailed specifications provided in technical tables.

• Q: What certifications support the cable’s performance claims?

  
  A: The cable is certified by recognized organizations such as EMAG and WUG, ensuring it meets stringent safety and performance standards.

• Q: Can this cable be used in both methane and non-methane mining areas?

  
  A: Yes, it is designed for safe operation in both methane and non-methane zones, accommodating various explosion risk classifications.

• Q: What kind of testing does the cable undergo before shipment?

  
  A: The cable undergoes rigorous testing including high-voltage endurance, mechanical stress tests, and conformity checks with international standards.

• Q: What maintenance practices are recommended for this cable in mining installations?

  
  A: Regular visual inspections, adherence to installation guidelines, and periodic testing of insulation and shielding integrity will help ensure long-term reliability.