-48v DC power - Doubling up breakers?

Discussion in 'Power Electronics' started by Rosko, Sep 20, 2016.

  1. Rosko

    Thread Starter New Member

    Mar 11, 2014
    Tough question to ask, let alone understand. So bare with me. This is for a problem in the telecommunications industry where -48v is common.

    Situation is: I have 2 independent 60 amp DC feeds. A Load(A) & a Load(B). Feeding a Load(A) and Load(B) distribution panel....feeding multiple pieces of equipment eaqch having redundant power. My current draw on each "leg" is about 45 amps for a total of 90 amps. My Independent feeds have two breaker positions. Currently only one on each leg being used by my 60 amp breakers. I need to add cards to my equipment and I anticipate it will bring my draw up to 55 amps on each leg for a total of 110 amps. I want to swap out my existing 60 amp breakers with 120 amps or bigger, but anything over a 100 amp takes two positions.

    Question: (starting with my Load A) If I added an additional 60 amp breaker and tied it directly from feed to distribution panel, would both my 60 amp breakers (on side A) hold the 90 amp load, while I remove the 60 amp breaker on side B and replace with 120 amp breaker.

    Assuming all my equipment will hold full load on half power ( load A or B) and no I cannot just depower things to make life easy.

  2. MaxHeadRoom


    Jul 18, 2013
    I draw the line at getting naked!

    But willing to 'Bear' with you. Is this a question that is related to the AC service breakers?
    It is not clear what power distribution you are asking about?
    ronv likes this.
  3. tcmtech

    Well-Known Member

    Nov 4, 2013
    Yes so long as the amp draw is less than the combined breaker ratings at the time.