elec master

Forum Replies Created

Viewing 2 posts - 1 through 2 (of 2 total)
  • Author
    Posts
  • in reply to: 3 Pole & 4Pole MCCB which one is suitable #12777
    elec master
    Participant

    i think this will depend if the electrical sources in your network will be considered as separately drived systems or not , for separately drived system , we must use 4 pole circuit breaker to disconnect the neutral of the two sources ( transformer and generators or 2 generators ) to prevent earth fault in the main switchgear.

     

    you can digg the NEC code for the expression ”  separately drived systems” and you will find the answer or got to the following site which explain the NEC code by following the link:

     

    Understanding NFPA 70 (National electrical code) course

    in reply to: Active Power Factor Correction in 3 phase AC supply #12776
    elec master
    Participant

    this done by adding power factor correction capacitors (PFCC) , you must know the following data:

    1- the load (kw) that you need to improve its power facto

    2- the old power factor value

    3- the new power factor value

     

    then you can use the power factor correction tables to calculate the required capacitor KVAR or using the PFCC calculation spread sheet which you can find it in this link:

    PFCC calculation spread sheet

     

    after you know the required KVAR, you must select the the capacitor sizes ,numbers and steps but you must defierntiate between electrical steps and the phisycal steps which i will explain it in a new reply.sorry , i must leave now.

Viewing 2 posts - 1 through 2 (of 2 total)