How to quickly estimate what percentage of cable cost is copper?
For common PVC power cables, copper cost accounts for 70-85% of total (varies with copper price).
Copper cost per meter formula: conductor weight(kg/m) × copper price(¥/kg)
Conductor weight(kg/m) = 8.89×10⁻⁶ × area(mm²) × cores (better: kg/km = 8.89×area×cores, then /1000)
Copper price significantly affects final cable price.
What is an ampacity table? How to read it?
An ampacity table gives the maximum current a cable can safely carry under specific conditions (ambient temp, installation method, conductor material). Example: IEC 60364-5-52 Table B.52.2.
How to read: Apply correction factors for actual conditions: ambient temperature, grouping, buried/in air, etc.
Source: IEC 60364-5-52.
What applications are suitable for 300/500V vs 450/750V rated cables?
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.
How to choose cable insulation material? Pros and cons of PVC, XLPE, TPU?
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 |
Which is better for vibration-prone environments: stranded or solid conductor?
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.
Can ordinary PVC cable be used outdoors inside conduit?
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.
inquiry
