ahmadalsayed20

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  • in reply to: help,plz #12552
    ahmadalsayed20
    Participant

    i already sent them to ur mail

    in reply to: help,plz #12526
    ahmadalsayed20
    Participant

    Dear Frechma,

     

    Send me your email and will send for a pdf file regarding what you need

    in reply to: CABLE SIZE #12520
    ahmadalsayed20
    Participant
    in reply to: CABLE SIZE #12499
    ahmadalsayed20
    Participant

    Dear Georges Ghali,

     

    I just wanted to ask if i want to size the main cable of the main distribution board ,should I consider the load current Ib   as the connected load current or the demanded current???? 

     

     

    Spir Georges GHALI said:

    Dear Ahmad ;

     

    It will be better to define the Standard that your are using in your country, if you use the ” IEC… “, please find below the method to define the Cable's Section.

     

    1- Calculate the Load's Current that we called ” Ib “.

    2- Accordingly to :

         – The methode oh installation of cable ” Barried  or  Unbarried ” and the type of installation for each one.

         – The number of the circuits laid togother.

         – The ambiant temperature.

       we will define the ” Correction Factors – k1, k2, … ” from the table of ” IEC 60364-5-52 “

    3- We calculate the Total Correction Factor ” k ” by multiplying all correction factors ” k = k1 x k2 x … “

    4- we calculate the nominal current for the cable in the working condition ” I’z ” by the formula : I’z = Ib / k “

    5- From the ” IEC 60364-5-52 ” tables that mentioned to the Nominal Current of each section in the Standard Conditions ” Iz ” depending on :

         – The ” methode oh installation “

         – The kind of cable ” Cu  or  Alu    ;   Single Core   or  Multi Cores    ;   PVC  or  XLPE “

        we will define the suitable cable's section where ” Iz ≥ I’z “.

    5- Then we calculate the Voltage Drop by the Formula : ” Δ V = 1.73 x I ( R . Cosφ  +  X . Sinφ ) “, where : R = ρ . L / S    ;    X = λ . L

    6- This value of the Voltage Drop should be smaller or equal than the value defined by ” IEC… ” ( 3% for Lighting   ;   5% for Machines ), if it's not the case, then the Cable's Section should be oversized.

    7- In the 1st & 2nd levels of the network where the values of the short circuit currents are important, it will be better to be sure that the cable can withstand the short circuit current during the tripping time of the protection device, where we use the formula : ” I² . t ≤ K² . S² “,

    if it's not the case, then the section of cable should be oversized.


    I just wanted to ask you, if i want to size a cable for a panel (main cable of the main distribution board)

     

    do i have to consider the current Ib as the currnet for connected load or demanded load ??

     

     

     

    Spir Georges GHALI said:

    Dear Ahmad ;

     

    It will be better to define the Standard that your are using in your country, if you use the ” IEC… “, please find below the method to define the Cable's Section.

     

    1- Calculate the Load's Current that we called ” Ib “.

    2- Accordingly to :

         – The methode oh installation of cable ” Barried  or  Unbarried ” and the type of installation for each one.

         – The number of the circuits laid togother.

         – The ambiant temperature.

       we will define the ” Correction Factors – k1, k2, … ” from the table of ” IEC 60364-5-52 “

    3- We calculate the Total Correction Factor ” k ” by multiplying all correction factors ” k = k1 x k2 x … “

    4- we calculate the nominal current for the cable in the working condition ” I’z ” by the formula : I’z = Ib / k “

    5- From the ” IEC 60364-5-52 ” tables that mentioned to the Nominal Current of each section in the Standard Conditions ” Iz ” depending on :

         – The ” methode oh installation “

         – The kind of cable ” Cu  or  Alu    ;   Single Core   or  Multi Cores    ;   PVC  or  XLPE “

        we will define the suitable cable's section where ” Iz ≥ I’z “.

    5- Then we calculate the Voltage Drop by the Formula : ” Δ V = 1.73 x I ( R . Cosφ  +  X . Sinφ ) “, where : R = ρ . L / S    ;    X = λ . L

    6- This value of the Voltage Drop should be smaller or equal than the value defined by ” IEC… ” ( 3% for Lighting   ;   5% for Machines ), if it's not the case, then the Cable's Section should be oversized.

    7- In the 1st & 2nd levels of the network where the values of the short circuit currents are important, it will be better to be sure that the cable can withstand the short circuit current during the tripping time of the protection device, where we use the formula : ” I² . t ≤ K² . S² “,

    if it's not the case, then the section of cable should be oversized.


    in reply to: CIRCUIT BREAKER SIZE #12417
    ahmadalsayed20
    Participant

    Thank You very much for your kind information

    Do you have any example regarding this matter please

    I appreciate your help

    in reply to: CIRCUIT BREAKER SIZE #12416
    ahmadalsayed20
    Participant

    Thank You very much for your kind information

    Do you have any example regarding this matter please

    I appreciate your help

    in reply to: CABLE SIZE #12489
    ahmadalsayed20
    Participant

    Spir Georges GHALI said:

    AHMAD ALSAYED said:

    MY EMAIL

     

    a_sayos20@hotmail.com


    Dear Ahmad ;

     

    I will send you an exemple.


    i will be waiting for your email

     

    thank you

    in reply to: CABLE SIZE #12488
    ahmadalsayed20
    Participant

    Thank you very much

    in reply to: Diversity factor #12483
    ahmadalsayed20
    Participant
Viewing 9 posts - 1 through 9 (of 9 total)