JB/T 10181.21-2014
Electric cables.Calculation of the current rating.Part 21: Thermal resistance.Calculation of thermal resistance (English Version)
- Standard No.
- JB/T 10181.21-2014
- Language
- Chinese, Available in English version
- Release Date
- 2014
- Published By
- Professional Standard - Machinery
- Latest
- JB/T 10181.21-2014
- Replace
- JB/T 10181.3-2000
- Scope
- This part of JB/T 10181 specifies the calculation method of cable thermal resistance. This section applies to AC cables of all voltage levels laid in the air or soil, and to the steady-state operating conditions of DC cables 5 kV and below. The soil includes cables laid directly buried in the ground, pipes, cable trenches or steel pipes with or without local soil drying. The term "steady state" refers to a continuous constant current (100% load factor) that is just sufficient to gradually reach the maximum temperature of the conductor, assuming constant ambient conditions. This section provides formulas for calculating thermal resistance. The values of some important parameters are not specified. Mainly divided into three categories of parameters: ——Parameters related to the cable structure (such as the thermal resistance coefficient of some insulating materials), representative values can be selected in public publications; ——Parameters related to environmental conditions, the value of which may change The range is larger and depends on the conditions of the laying site where the cable is used or where the cable will be used; ——parameters negotiated between the manufacturer and the user, including the operating safety margin (such as the maximum conductor temperature).
JB/T 10181.21-2014 history
- 2014 JB/T 10181.21-2014 Electric cables.Calculation of the current rating.Part 21: Thermal resistance.Calculation of thermal resistance
- 2000 JB/T 10181.3-2000 Calculation of the current rating of electric cables.Part 2:Thermal resistance.Section 1:Calculation of thermal resistance
JB/T 10181.21-2014 Electric cables.Calculation of the current rating.Part 21: Thermal resistance.Calculation of thermal resistance has been changed from JB/T 10181.3-2000 Calculation of the current rating of electric cables.Part 2:Thermal resistance.Section 1:Calculation of thermal resistance.
