Installation Method A2

The standard IEC 60364-5-52 in paragragh B.52.6.1 Reference methods specifies:

Reference methods A1, item 1 of Table A.52.3 (insulated conductors in conduit in a thermally insulated wall) and A2, item 2 of Table A.52.3, (multi-core cable in conduit in a thermally insulated wall):

The wall consists of an outer weatherproof skin, thermal insulation and an inner skin of wood or wood-like material having a thermal conductance of at least 10 W/m2·K.
The conduit is fixed so as to be close to, but not necessarily touching the inner skin.
Heat from the cables is assumed to escape through the inner skin only.
The conduit can be metal or plastic.

Blueprint sample project

Sample project

This is a sample electrical project in which cables are sized according to IEC 60364-5-52 and the methods of installation specified in it. The project file must be first unzipped and then openned using TiSoft ElectricalDesign. If you don't have it, you can download a fully functional 3-days demo.

Download

Example of sizing cable

Electrical load named LOAD 2 is fed by Circuit 2 of switchboard DB2 3~400V as shown in Fig. 1 below

Load given data

  • Installed power P = 3.0 kW
  • Power factor p.f(cosφ) = 0.85
  • Number of Phases: 1
  • Line to neutral voltage U = 231 V
  • Load current Ib = 15.3A (calculated Ib=P/(U*cosφ))
  • Protective device rated current MCB In=16A (Sized from condition In > Ib)
  • Cable given data

    • Cable type: Copper conductor, PVC insulation, PVC sheath, harmonized deignation H05VV
    • Installation Method: In plastic conduits inside the wall
    • Number of circuits in the conduit: 3
    • Room temperature: 35 °C
    • Length L=15 m
    • Permitted voltage drop ΔU = 2 %

    Fig.1. Grid with circuits of distribution board DB2, Circuit 2 in red rectangle

    Select the cable

    From the Cables library of ElectricalDesign select the cable with the smallest cross-section.


    Solution

    On circuits list, select the cable and click (see Fig.1) to open the dialog IEC 60364-5-52, Select cable type and Method of Installation (see Fig.2) and follow the steps below.

    Step 1, Cable type

    Select H05VV from the drop-down list.

    Step 2, Number of cores

    Choose 3.

    Step 3, Method of Installation

    • First, select the Reference method A2: Multi-corecables in conduit in a thermally insulated wall
    • Second, click button b and from dialog box (see Fig.3) select Item Number 2
    • Number of circuit or multi-core cables = 3

    Step 4, Reduction factors

    • Air temperature = 35 °C
    • Bounched in air, on a surface

    Step 5, Cable sizing

    Choose Automatically.

    Fig. 2 IEC 60364-5-52, Select cable type and Method of Installation Dialog

    Fig. 3 IEC 60364-5-52, Select Installation Method Item No

    The grid at the left bottom of the form is populated with:

    • Cable designations of cable type H05VV 3-core from Cables library
    • Ir=Current carrying capacity in Amperes, obtained from column 3 of Table B.52.2 of the standard

    The correction factors are obtained from:

    • Correction factor k1 =0.94 from Table B.52.14, for
      • Air temperature = 35 °C and
      • PVC insulation
    • Correction factor k2 =0.70 from from Table B.52.17 for
      • Number of circuits = 3 and
      • Bunched in air

    Looking for the smallest cross-section

    The program checks all cables one-by-one - starting from the smallest cross-section - looking for a cross-section that satisfies the condition
    Iz = Ir*k1*k2 > In

    • The cross-section 2.5 mm2 that has Iz = 18.5*0.94*0.70 = < 16 A is rejected
    • The next cross-section 4 mm2 that has Iz = 25*0.94*0.70 = 16.5 > 16 A is accepted

    The Cable found

    Is H05VV-U 3G4

    Useful downloads

    Circuit-2-Line analytical calculations according to IEC 60364 (pdf)

    Switchboard bill of quantities (pdf)

    Switchboard list of material (pdf)

    Switchboard single-line diagram (pdf)

    Switchboard voltage-drop-check diagram (pdf)

    Switchboard short-circuit-calculation diagram (pdf)

Installation Method A2

The standard IEC 60364-5-52 in paragragh B.52.6.1 Reference methods specifies:

Reference methods A1, item 1 of Table A.52.3 (insulated conductors in conduit in a thermally insulated wall) and A2, item 2 of Table A.52.3, (multi-core cable in conduit in a thermally insulated wall):

The wall consists of an outer weatherproof skin, thermal insulation and an inner skin of wood or wood-like material having a thermal conductance of at least 10 W/m2·K.
The conduit is fixed so as to be close to, but not necessarily touching the inner skin.
Heat from the cables is assumed to escape through the inner skin only.
The conduit can be metal or plastic.

Blueprint sample project

Sample project

This is a sample electrical project in which cables are sized according to IEC 60364-5-52 and the methods of installation specified in it. The project file must be first unzipped and then openned using TiSoft ElectricalDesign. If you don't have it, you can download a fully functional 3-days demo.

Download

Example of sizing cable

Electrical load named LOAD 2 is fed by Circuit 2 of switchboard DB2 3~400V as shown in Fig. 1 below

Load given data

  • Installed power P = 3.0 kW
  • Power factor p.f(cosφ) = 0.85
  • Number of Phases: 1
  • Line to neutral voltage U = 231 V
  • Load current Ib = 15.3A (calculated Ib=P/(U*cosφ))
  • Protective device rated current MCB In=16A (Sized from condition In > Ib)
  • Cable given data

    • Cable type: Copper conductor, PVC insulation, PVC sheath, harmonized deignation H05VV
    • Installation Method: In plastic conduits inside the wall
    • Number of circuits in the conduit: 3
    • Room temperature: 35 °C
    • Length L=15 m
    • Permitted voltage drop ΔU = 2 %

    Fig.1. Grid with circuits of distribution board DB2, Circuit 2 in red rectangle

    Select the cable

    From the Cables library of ElectricalDesign select the cable with the smallest cross-section.


    Solution

    On circuits list, select the cable and click (see Fig.1) to open the dialog IEC 60364-5-52, Select cable type and Method of Installation (see Fig.2) and follow the steps below.

    Step 1, Cable type

    Select H05VV from the drop-down list.

    Step 2, Number of cores

    Choose 3.

    Step 3, Method of Installation

    • First, select the Reference method A2: Multi-corecables in conduit in a thermally insulated wall
    • Second, click button b and from dialog box (see Fig.3) select Item Number 2
    • Number of circuit or multi-core cables = 3

    Step 4, Reduction factors

    • Air temperature = 35 °C
    • Bounched in air, on a surface

    Step 5, Cable sizing

    Choose Automatically.

    Fig. 2 IEC 60364-5-52, Select cable type and Method of Installation Dialog

    Fig. 3 IEC 60364-5-52, Select Installation Method Item No

    The grid at the left bottom of the form is populated with:

    • Cable designations of cable type H05VV 3-core from Cables library
    • Ir=Current carrying capacity in Amperes, obtained from column 3 of Table B.52.2 of the standard

    The correction factors are obtained from:

    • Correction factor k1 =0.94 from Table B.52.14, for
      • Air temperature = 35 °C and
      • PVC insulation
    • Correction factor k2 =0.70 from from Table B.52.17 for
      • Number of circuits = 3 and
      • Bunched in air

    Looking for the smallest cross-section

    The program checks all cables one-by-one - starting from the smallest cross-section - looking for a cross-section that satisfies the condition
    Iz = Ir*k1*k2 > In

    • The cross-section 2.5 mm2 that has Iz = 18.5*0.94*0.70 = < 16 A is rejected
    • The next cross-section 4 mm2 that has Iz = 25*0.94*0.70 = 16.5 > 16 A is accepted

    The Cable found

    Is H05VV-U 3G4

    Useful downloads

    Circuit-2-Line analytical calculations according to IEC 60364 (pdf)

    Switchboard bill of quantities (pdf)

    Switchboard list of material (pdf)

    Switchboard single-line diagram (pdf)

    Switchboard voltage-drop-check diagram (pdf)

    Switchboard short-circuit-calculation diagram (pdf)