faq

• Q

  What applications are suitable for 300/500V vs 450/750V rated cables?

  A

  300/500V: household and light appliances (indoor lighting, sockets), e.g., RVV, RVS.
  450/750V: power wiring, industrial distribution, fixed power lines, e.g., BV, BVR, VV.
  Operating voltage shall not exceed U0/U rating.

  Source: IEC 60227 & national standards.

• Q

  How to choose cable insulation material? Pros and cons of PVC, XLPE, TPU?

  A

  Material	Advantages	Disadvantages	Typical use
  PVC	cheap, flexible, flame retardant	low temp rating, not UV-stable, toxic gas	general indoor
  XLPE	high temp rating, good electrical	stiffer	power cables
  TPU	high abrasion/oil/low-temp/flex	expensive (3-5×PVC)	drag chain, robots

  
  

• Q

  Which is better for vibration-prone environments: stranded or solid conductor?

  A

  Stranded conductor. Solid conductor is prone to fatigue fracture under repeated bending or vibration. Stranded consists of many fine wires that distribute stress, offering better flex life and vibration resistance.
  Used in: robots, automotive harnesses, marine equipment.

  Source: Mechanical fatigue principles.

• Q

  Can ordinary PVC cable be used outdoors inside conduit?

  A

  Not recommended. Even inside conduit, condensation can accumulate, keeping PVC wet and accelerating plasticizer migration and hydrolysis. Temperature cycling also promotes cracking.
  Use at least weather-resistant PVC (PVC-ST2), PE, or XLPE for outdoor applications.

  Source: Cable selection guidelines.

• Q

  What causes cable sheath cracking after a few years of outdoor use?

  A

        UV radiation (PVC not UV-stable)

        Low-temperature embrittlement (PVC brittle below -15°C)

        Thermo-oxidative ageing

        Plasticizer migration (moisture or chemicals)

        Mechanical stress (tight bending or tension)

  Solution: use weather-resistant materials (XLPE, TPU, PE, or weather-resistant PVC).

  Source: Polymer ageing studies.

• Q

  How much larger should aluminum cable be compared to copper for the same ampacity?

  A

  Aluminum conductivity ≈ 61% of copper (IACS). For same ampacity, aluminum cross-section ≈ 1.6× copper.
  Example: copper 10mm² → aluminum 16mm².
  Note: Voltage drop is higher; termination must be bi-metallic to avoid oxidation and creep.

  Source: IACS standard & engineering practice.