Question about an old powersupply

Discussion in 'General Electronics Chat' started by opa627bm, Nov 26, 2011.

  1. opa627bm

    Thread Starter New Member

    Nov 26, 2011
    Hi everyone,

    I bought a very old logic analyzer and I took it apart few days ago. I extracted a huge power supply from it and I found a really strange design in the unit.
    From the tag, we know that it can output +5.35V @65A. However, I noticed that the actual terminal is labeled as -5.35V. I think they connected COMM as +5.35V and -5.35V as GND.
    My question is, why they labeled it that way? Is that because N type conducts current better?

    Thanks and Best Regard
  2. SgtWookie


    Jul 17, 2007
    They might have done that in an attempt to avoid confusion with the other outputs' common terminal. Marked this way, the 5.35 output is between the two common terminals.

    I am assuming that the 5.35v output is isolated from the other outputs, and therefore it could be connected as either a positive or negatively referenced output - or perhaps completely independent.
  3. paulktreg

    Distinguished Member

    Jun 2, 2008
    The -5.35V terminal appears to be connected to -ve terminals of the electrolytic capacitor bank behind it with the +ve's connected to COMM so perhaps in a true sense it is a negative supply?