Connect with us

PC Power supply question...

Discussion in 'Electronic Basics' started by J Shrum, Mar 16, 2005.

Scroll to continue with content
  1. J Shrum

    J Shrum Guest

    I've been using a 250W PC power supply as a bench supply.
    Question:
    The ratings are on the label stating 12V - 7.5A surge.
    So if 7.5A is the absolute max, what would I expect the RMS to be? I'm
    running it into a flyback w/ a primary resistance of like 1ohm... I assume
    I'll have to throw a high wattage resistor in there to bring down the
    current through the primary, but what is the most that I can *safely* draw
    from this supply @ 12v.

    Thanks...

    Jim
    KC9FFX
     
  2. Tom Biasi

    Tom Biasi Guest

    Hi Jim,
    Usually the PS units have a maximum rating and a rating for each supply
    voltage.
    I haven't seen a 'surge' rating on a PC supply only a maximum output.
    Since you are using only the 12 V. section you would need to respect the
    rating for that section.
    If indeed your unit specs a surge then the continuous will be less than
    that.
    Since 12 V. with a 1 ohm load draws 12 Amps continuous, I think that we can
    *safely* say you are exceeding the limits of the PS :)
    A 7.5 A. surge could be 5A continuous or less.
    Regards,
    Tom
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-